Formulation of Polymeric Nanoparticles Loading Baricitinib as a Topical Approach in Ocular Application.

Topical ocular drug delivery faces several challenges due to the eye's unique anatomy and physiology. Physiological barriers, tear turnover, and blinking hinder the penetration of drugs through the ocular mucosa. In this context, nanoparticles offer several advantages over traditional eye drops.

PLGA Nanoparticles Containing Natural Flavanones for Ocular Inflammation.

Flavanones are natural compounds that display anti-inflammatory activity. The aim of this work was to prepare PLGA nanoparticles (NPs) containing natural flavanones I ((2)-5,7-dihydroxy-6-methyl-8-(3-methyl-2-buten-1-il)-2-phenyl-2,3-dihydro-4-1-Benzopyran-4-one) and II (2)-5,7-dihydroxy-2-(4'-methoxyphenyl)-6-methyl-8-(3-methyl-2-buten-1-yl)-2,3-dihydro-4-1-Benzopyran-4-one) (NP I and NP II, respectively) so as to evaluate their potential for topical anti-inflammatory ocular therapy. An in silico study was carried out using the Molinspiration and PASS Online web platforms before evaluating the in vitro release study and the ex vivo porcine cornea and sclera permeation.

Defined covalent attachment of three cancer drugs to DNA origami increases cytotoxicity at nanomolar concentration.

DNA nanostructures have captured great interest as drug delivery vehicles for cancer therapy. Despite rapid progress in the field, some hurdles, such as low cellular uptake, low tissue specificity or ambiguous drug loading, remain unsolved. Herein, well-known antitumor drugs (doxorubicin, auristatin, and floxuridine) were site-specifically incorporated into DNA nanostructures, demonstrating the potential advantages of covalently linking drug molecules via structural staples instead of incorporating the drugs by noncovalent binding interactions.

Baricitinib Lipid-Based Nanosystems as a Topical Alternative for Atopic Dermatitis Treatment.

Atopic dermatitis (AD) is a chronic autoimmune inflammatory skin disorder which causes a significant clinical problem due to its prevalence. The ongoing treatment for AD is aimed at improving the patient's quality of life. Additionally, glucocorticoids or immunosuppressants are being used in systemic therapy.

On the uptake of cationic liposomes by cells: From changes in elasticity to internalization.

In this study, we assessed the capacity of a previously reported engineered liposomal formulation, which had been tested against model membranes mimicking the lipid composition of the HeLa plasma membrane, to fuse and function as a nanocarrier in cells. We used atomic force microscopy to observe physicochemical changes on the cell surface and confocal microscopy to determine how the liposomes interact with cell membranes and released their load. In addition, we performed viability assays using methotrexate as an active drug to obtain proof of concept of the formulation´s capacity to function as a drug delivery-system.

Studying Lipid Membrane Interactions of a Super-Cationic Peptide in Model Membranes and Living Bacteria.

The super-cationic peptide dendrimers (SCPD) family is a valuable class of antimicrobial peptide candidates for the future development of antibacterial agents against multidrug-resistant gram-negative bacteria. The deep knowledge of their mechanism of action is a major challenge in research, since it may be the basis for future modifications/optimizations. In this work we have explored the interaction between SCPD and membranes through biophysical and microbiological approaches in the case of the G1OLO-LOL peptide.

Assessment of Efficacy and Safety Using PPAR-γ Agonist-Loaded Nanocarriers for Inflammatory Eye Diseases.

Drug-loaded nanocarriers (NCs) are new systems that can greatly improve the delivery and targeting of drugs to specific tissues and organs. In our work, a PPAR-γ agonist loaded into polymeric NCs was prepared, stabilized by spray-drying, and tested in vitro, ex vivo, and in vivo (animal models) to provide a safe formulation for optical anti-inflammatory treatments. The NCs were shown to be well tolerated, and no signs of irritancy or alterations of the eye properties were detected by the in vitro HET-CAM test and in vivo Draize test.

Baricitinib Liposomes as a New Approach for the Treatment of Sjögren's Syndrome.

Sjögren's syndrome is a chronic systemic autoimmune disease affecting from 0.2 to 3% of the general population. The current treatment for Sjögren's syndrome is aimed at controlling symptoms such as dry eyes and xerostomia.

Endogenous Antioxidant Cocktail Loaded Hydrogel for Topical Wound Healing of Burns.

The main goal of this work is the study of the skin wound healing efficacy of an antioxidant cocktail consisting of vitamins A, D, E and the endogenous pineal hormone melatonin (MLT), with all of these loaded into a thermosensitive hydrogel delivery system. The resulting formulation was characterized by scanning electron microscopy. The antioxidant efficacy and microbiological activity against Gram positive and Gram negative strains were also assayed.

Characterization of monolayers and liposomes that mimic lipid composition of HeLa cells.

In this work, based on several studies, we develop an artificial lipid membrane to mimic the HeLa cell membrane using 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE), 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS) and cholesterol (CHOL). This is then a means to further study the fusion process of specific engineered liposomes. To characterize the mimicked HeLa cell membrane, we determined a series of surface pressure-area (π-A) isotherms and the isothermal compression modulus was calculated together with the dipole moment normal to the plane of the monolayer.

Topical Pioglitazone Nanoformulation for the Treatment of Atopic Dermatitis: Design, Characterization and Efficacy in Hairless Mouse Model.

Pioglitazone (PGZ) is a drug used to treat type 2 diabetes mellitus that has been reported to show additional therapeutic activities on diverse inflammatory parameters. The aim of this study was to optimize a topical PGZ-loaded nanoemulsion (PGZ-NE) in order to evaluate its effectiveness for treating atopic dermatitis (AD). The composition of the nanoformulation was established by pseudo-ternary diagram.

Thermoreversible Gel-Loaded Amphotericin B for the Treatment of Dermal and Vaginal Candidiasis.

The present study was designed to develop a thermoreversible gel of Pluronic (P407) loaded amphotericin B (AmB-gel) for the dermal and vaginal treatment of candidiasis. P407 was used as a copolymer to exploit potential advantages related to increasing drug concentration in the tissue layer in order to provide a local effect. Parameters including internal structure, swelling, porosity, and short-term stability were determined.

Planar lipid bilayers formed from thermodynamically-optimized liposomes as new featured carriers for drug delivery systems through human skin.

The fundamental objective pursued in this work is to investigate how liposomes formed with a thermodynamically optimized molar composition formed by the main components of the stratum corneum matrix behave on the human skin surface when used as drug delivery systems. To this purpose we engineered liposomes using phosphatidylcholines, ceramides and cholesterol. The specific molar ratio of the three components was established after studying the mixing properties of the lipid monolayers of the lipid components formed at the air-water interface.

Effect of cholesterol on monolayer structure of different acyl chained phospholipids.

In this work we have investigated the effect of cholesterol (CHOL) in phospholipid monolayers on a series of phosphatidylcholines differing in acyl chain composition. We have used the CHOL proportion that abolishes the gel (L)-to-liquid-crystalline (L) transition in bilayers in order to investigate the mixing properties and laterally-segregated domains formed by specific phospholipid-CHOL ratios at the air-water interface. The binary monolayers where formed by mixing CHOL with 1,2-palmitoyl-sn-glycero-3-phos-phatidylcholine (DPPC);1,2-distearoyl-sn-glycero-3-phosphatidylcholine (DSPC); 1-pal-mitoyl-2-stearoyl-sn-glycero-3-phosphatidylcholine (PSPC); 1-palmitoyl-2-oleoyl-sn-gly-cero-3-phosphatidylcholine (POPC) and 1-palmitoyl-2-linoleyl-sn-glycero-3-phosphatidyl-choline (PLPC), respectively.

Multidisciplinary Approach to the Transfection of Plasmid DNA by a Nonviral Nanocarrier Based on a Gemini-Bolaamphiphilic Hybrid Lipid.

A multidisciplinary strategy, including both biochemical and biophysical studies, was proposed here to evaluate the potential of lipid nanoaggregates consisting of a mixture of a gemini-bolaamphiphilic lipid (CCC) and the well-known helper lipid 1,2-dioleoyl--glycero-3-phosphatidylethanolamine (DOPE) to transfect plasmid DNA into living cells in an efficient and safe way. For that purpose, several experimental techniques were employed, such as zeta potential (phase analysis light scattering methodology), agarose gel electrophoresis (pDNA compaction and pDNA protection assays), small-angle X-ray scattering, cryo-transmission electron microscopy, atomic force microscopy, fluorescence-assisted cell sorting, luminometry, and cytotoxicity assays. The results revealed that the cationic lipid and plasmid offer only 70 and 30% of their nominal positive () and negative charges (), respectively.

Amphotericin B releasing topical nanoemulsion for the treatment of candidiasis and aspergillosis.

The present study was designed to develop a nanoemulsion formulation of Amphotericin B (AmB) for the treatment of skin candidiasis and aspergillosis. Several ingredients were selected on the basis of AmB solubility and compatibility with skin. The formulation that exhibited the best properties was selected from the pseudo-ternary phase diagram.

Critical Temperature of 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine Monolayers and Its Possible Biological Relevance.

Because transmembrane proteins (TMPs) can be obtained with sufficient purity for X-ray diffraction studies more frequently than decades ago, their mechanisms of action may now be elucidated. One of the pending issues is the actual interplay between transmembrane proteins and membrane lipids. There is strong evidence of the involvement of specific lipids with some membrane proteins, such as the potassium crystallographically sited activation channel (KcsA) of Streptomyces lividans and the secondary transporter of lactose LacY of Escherichia coli, the activities of which are associated with the presence of anionic phospholipids such as the phosphatidylglycerol (PG) and phosphatidyethanolamine (PE), respectively.

A biophysical study of gene nanocarriers formed by anionic/zwitterionic mixed lipids and pillar[5]arene polycationic macrocycles.

The use of divalent cations as mediators between anionic lipids (ALs) and nucleic acids has been explored for several years in gene therapy. However, a promising anionic lipid system which could surpass the outcomes of current cationic lipids (CLs) has not been found yet. One plausible reason for such poor efficiencies may be the impossibility of AL-DNA lipoplexes mediated by divalent cations to reach charge inversion, in contrast with the usual behavior of CL-DNA lipoplexes.

Mapping phase diagrams of supported lipid bilayers by atomic force microscopy.

In this work, we present the method followed to construct a pseudophase diagram of two phospholipids: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol). Two different techniques, DSC and AFM, have been used based in the determination of the onset (T ) and completion (T ) temperatures of the gel-to-liquid crystalline phases (L →L ), the first from the endotherms from liposomes and the second from the topographic images of supported lipid bilayers. The features of both phase diagrams are discussed emphasizing the influence of Ca presence and the substrate (mica) on the transition undergone by the phospholipid mixture.

Biofilm formation on polystyrene in detached vs. planktonic cells of polyhydroxyalkanoate-accumulating Halomonas venusta.

Biofilm development is characterized by distinct stages of initial attachment, microcolony formation and maturation (sessile cells), and final detachment (dispersal of new, planktonic cells). In this work we examined the influence of polyhydroxyalkanoate (PHA) accumulation on bacterial surface properties and biofilm formation on polystyrene in detached vs. planktonic cells of an environmental strain isolated from microbial mats, Halomonas venusta MAT28.

Enhanced topical delivery of hyaluronic acid encapsulated in liposomes: A surface-dependent phenomenon.

In the present study, we investigated the release and permeation of hyaluronic acid (HA) encapsulated in liposomes when deposited onto two surfaces: cellulose, a model widely used for investigating transport of drugs; and human skin, a natural biointerface used for transdermal drug delivery. We prepared and characterised liposomes loaded with HA and liposomes incorporating two penetration enhancers (PEs): the non-ionic surfactant Tween 80, and Transcutol P, a solubilising agent able to mix with polar and non-polar solvents. In vitro and ex vivo permeation assays showed that PEs indeed enhance HA-release from liposomes.

Polycationic Macrocyclic Scaffolds as Potential Non-Viral Vectors of DNA: A Multidisciplinary Study.

The potential of lipoplexes constituted by the DNA pEGFP-C3 (encoding green fluorescent protein), polycationic calixarene-based macrocyclic vector (CxCL) with a lipidic matrix (herein named TMAC4), and zwitterionic lipid 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) as nontoxic DNA vectors has been analyzed from both biophysical and biochemical perspectives. For that purpose, several experimental methods, such as zeta potential (PALS methodology), agarose gel electrophoresis, small-angle X-ray scattering (SAXS), transmission electronic cryo-microscopy (cryo-TEM), atomic force microscopy (AFM), fluorescence microscopy, and cytotoxicity assays have been used. The electrochemical study shows that TMAC4 has 100% of its nominal charge available, whereas pDNA presents an effective negative charge that is only 10% that of its nominal one.

Unspecific membrane protein-lipid recognition: combination of AFM imaging, force spectroscopy, DSC and FRET measurements.

In this work, we will describe in quantitative terms the unspecific recognition between lactose permease (LacY) of Escherichia coli, a polytopic model membrane protein, and one of the main components of the inner membrane of this bacterium. Supported lipid bilayers of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG) (3:1, mol/mol) in the presence of Ca(2+) display lateral phase segregation that can be distinguished by atomic force microscopy (AFM) as well as force spectroscopy. LacY shows preference for fluid (Lα) phases when it is reconstituted in POPE : POPG (3:1, mol/mol) proteoliposomes at a lipid-to-protein ratio of 40.

Domain formation and permeabilization induced by the saponin α-hederin and its aglycone hederagenin in a cholesterol-containing bilayer.

Saponins and triterpenic acids have been shown to be able to interact with lipid membranes and domains enriched with cholesterol (rafts). How saponins are able to modulate lipid phase separation in membranes and the role of the sugar chains for this activity is unknown. We demonstrate in a binary membrane model composed of DMPC/Chol (3:1 mol/mol) that the saponin α-hederin and its aglycone presenting no sugar chain, the triterpenic acid hederagenin, are able to induce the formation of lipid domains.

Improving ex vivo skin permeation of non-steroidal anti-inflammatory drugs: enhancing extemporaneous transformation of liposomes into planar lipid bilayers.

Transdermal delivery of active principles is a versatile method widely used in medicine. The main drawback for the transdermal route, however, is the low efficiency achieved in the absorption of many drugs, mostly due to the complexity of the skin barrier. To improve drug delivery through the skin, we prepared and characterized liposomes loaded with ibuprofen and designed pharmaceutical formulations based on the extemporaneous addition of penetration enhancer (PE) surfactants.