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Staphylococcus aureus infections and its biofilm removal is an important concern in health care management. Methicillin-resistant S. aureus is responsible for severe morbidity and mortality worldwide. The extensive use of disinfectants against biofilms has led to negative environmental impacts. Developing new and more potent biofilm eradication agents with minimal detrimental effects on human and environmental health is currently on the agenda. The alkyl esters of L-ascorbic acid (ASCn) are antioxidant amphiphiles, which show antimicrobial capacity against methicillin-sensitive and resistant S. aureus strains. ASC12 and ASC14 formulations are able to kill the persister cells of the deepest layers of the biofilm. We tested the hypothesis that the antimicrobial and antibiofilm capacity found for the ASCn emerges from a combined effect of its amphiphilic and their redox capacity. This mechanism appears related to: I) a larger diffusion capacity of the ASC12 micelles than ASC14 and ASC16 microstructures; II) the neutralization of the ASCn acid hydroxyl when the amphiphile reaches the surface of an anionic surface, followed by a rapid insertion; III) the disruption of cell membrane by alteration of membrane tension and structure and IV) ASCn accumulation in the cell membrane or biofilm extracellular matrix surfaces, reducing functional chemical groups and affecting its biological function.

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Ketoconazole (Ke) is an important antifungal drug, and two of its diphenylphosphinemethyl derivatives (KeP: Ph2PCH2-Ke and KeOP: Ph2P(O)CH2-Ke) have shown improved antifungal activity, namely against a yeast strain lacking ergosterol, suggesting alternative modes of action for azole compounds. In this context, the interactions of these compounds with a model of the cell membrane were investigated, using POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) large unilamellar vesicles and taking advantage of the intrinsic fluorescence of Ke, KeP and KeOP. Steady-state fluorescence spectra and anisotropy, including partition and aggregation studies, as well as fluorescence lifetime measurements, were carried out. In addition, the ability of the compounds to increase membrane permeability was assessed through carboxyfluorescein leakage. The membrane/water mole fraction partition coefficients (Kp,x): (3.31 ± 0.36) x105, (8.31 ± 1.60) x105 and (4.66 ± 0.72) x106, for Ke, KeP and KeOP, respectively, show that all three compounds have moderate to high affinity for the lipid bilayer. Moreover, KeP, and particularly KeOP interact more efficiently with POPC bilayers than Ke, which correlates well with their in vitro antifungal activity. Furthermore, although the three compounds disturb the lipid bilayer, KeOP is the quickest and most efficient one. Hence, the higher affinity and ability to permeabilize the membrane of KeOP when compared to that of KeP, despite the higher lipophilicity of the latter, points to an important role of Ph2P(O)CH2- oxygen. Overall, this work suggests that membrane interactions are important for the antifungal activity of these azoles and should be considered in the design of new therapeutic agents.

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HYPOTHESIS: The antidepressant drug imipramine, and its metabolite desipramine show different extents of interaction with, and passive permeation through, cellular membrane models, with the effects depending on the membrane composition. Through multimodal interrogation, we can observe that the drugs have a direct impact on the physicochemical properties of the membrane, that may play a role in their pharmacokinetics. EXPERIMENTS: Microcavity pore-suspended lipid bilayers (MSLBs) of four different compositions, each with a different headgroup charge namely; zwitterionic dioleoylphosphatidylcholine (DOPC), mixed DOPC and negatively charged dioleoylphosphatidylglycerol (DOPG) (3:1), mixed DOPC and positively charged dioleoyltrimethylammoniumpropane (DOTAP) (3:1), and with increasing complex composition mimicking blood-brain-barrier (BBB) were prepared on gold and polydimethylsiloxane (PDMS) substrates using a Langmuir-Blodgett-vesicle fusion method. The molecular interaction and permeation of antidepressants, imipramine, and its metabolite desipramine with the lipid bilayers were evaluated using highly sensitive label-free electrochemical impedance spectroscopy (EIS) and surface-enhanced Raman spectroscopy (SERS). Drug-induced membrane packing/fluidity alterations were assessed using fluorescence lifetime imaging (FLIM) and fluorescence lifetime correlation spectroscopy (FLCS) of MSLB over microfluidic PDMS array. FINDINGS: Using EIS to evaluate in real-time membrane admittance changes, we found that imipramine greatly increases the ion permeability of negatively charged DOPC:DOPG (3:1) membranes. The effect was observed also at neutral (DOPC) and to a lesser extent at positively charged DOPC:DOTAP(3:1) membranes. In contrast, desipramine had a much weaker impact on ion permeability across all bilayer compositions. Temporal capacitance data show that desipramine intercalates at negatively charged membrane thereby increasing the thickness of the membrane. The overall kinetics of the imipramine permeation is higher than that of desipramine. This was confirmed using SERS, which also provides an evaluation of drug passive permeation based on arrival time across the membrane. Using FLCS, we found that imipramine increases the lipid membrane fluidity, whereas desipramine lowers it, with the exception of the negatively charged membrane. A translocation rate pharmacokinetics model was established for the first time at the MSLB platform by real-time monitoring of the variation in membrane resistance of pristine DOPC and blood-brain-barrier (BBB) membrane.

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The purpose of the present paper was to assess the ability of five newly designed and synthesized meloxicam analogues to interact with phospholipid bilayers. Calorimetric and fluorescence spectroscopic measurements revealed that, depending on the details of the chemical structure, the studied compounds penetrated bilayers and affected mainly their polar/apolar regions, closer to the surface of the model membrane. The influence of meloxicam analogues on the thermotropic properties of DPPC bilayers was clearly visible because these compounds reduced the temperature and cooperativity of the main phospholipid phase transition. Additionally, the studied compounds quenched the fluorescence of prodan to a higher extent than laurdan, what pointed to a more pronounced interaction with membrane segments close to its surface. We presume that a more pronounced intercalation of the studied compounds into the phospholipid bilayer may be related to the presence of the molecule of a two-carbon aliphatic linker with a carbonyl group and fluorine substituent/trifluoromethyl group (compounds PR25 and PR49) or the three-carbon linker together with the trifluoromethyl group (PR50). Moreover, computational investigations of the ADMET properties have shown that the new meloxicam analogues are characterized by beneficial expected physicochemical parameters, so we may presume that they will have a good bioavailability after an oral administration.

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Despite the widespread and easy access to NSAIDs, effective and safe treatment of various inflammatory disorders is still a serious challenge because of the severe adverse effects distinctive to these drugs. The Mannich base derivatives of pyrrolo[3,4-c]pyrrole are potent, preferential COX-2 inhibitors with a COX-2/COX-1 inhibitory ratio better than meloxicam. Therefore, we chose the six most promising molecules and subjected them to further in-depth research. The current study presents the extensive biological, spectroscopic and in silico evaluation of the activity and physicochemical properties of pyrrolo[3,4-c]pyrrole derivatives. Aware of the advantages of dual COX-LOX inhibition, we investigated the 15-LOX inhibitory activity of these molecules. We also examined their antioxidant effect in several in vitro experiments in a protection and regeneration model. Furthermore, we defined how studied compounds interact with artificial models of cell membranes, which is extremely important for drugs administered orally with an intracellular target. The interactions and binding mode of the derivatives with the most abundant plasma proteins-human serum albumin and alpha-1-acid glycoprotein-are also described. Finally, we used computational techniques to evaluate their pharmacokinetic properties. According to the obtained results, we can state that pyrrolo[3,4-c]pyrrole derivatives are promising anti-inflammatory and antioxidant agents with potentially good membrane permeability.

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Ruscogenin, a kind of steroid saponin, has been shown to have significant anti-oxidant, anti-inflammatory, and anti-thrombotic characteristics. Furthermore, it has the potential to be employed as a medicinal medication to treat a variety of acute and chronic disorders. The interaction of a drug molecule with cell membranes can help to elucidate its system-wide protective and therapeutic effects, and it's also important for its pharmacological activity. The molecular mechanism by which ruscogenin affects membrane architecture is still a mystery. Ruscogenin's interaction with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) and anionic dipalmitoyl phosphatidylglycerol (DPPG) multilamellar vesicles (MLVs) was studied utilizing two non-invasive approaches, including: Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry. Ruscogenin caused considerable alterations in the phase transition profile, order, dynamics and hydration state of head groups and glycerol backbone of DPPC and DPPG MLVs at all concentrations. The DSC results indicated that the presence of ruscogenin decreased the main phase transition temperature (Tm) and enthalpy (ΔH) values of both membranes and increased half height width of the main transition (ΔT1/2). The FTIR results demonstrated that all concentrations (1, 3, 6, 9, 15, 24 and 30 mol percent) of ruscogenin disordered the DPPC MLVs both in the gel and liquid crystalline phases while it increased the order of DPPG MLVs in the liquid crystalline phase. Moreover, ruscogenin caused an increase in the dynamics of DPPC and DPPG MLVs in both phases. Additionally, it enhanced the hydration of the head groups of lipids and the surrounding water molecules implying ruscogenin to interact strongly with both zwitterionic and charged model membranes.

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Cytisine (CYT) is a powerful anti-smoking compound which could greatly benefit from transbuccal delivery because of both its unfavorable pharmacokinetics after oral administration and its intrinsic ability to permeate the buccal mucosa. This work aims to design CYT-loaded buccal thin films suitable for transbuccal drug delivery due to its capability of promoting the interaction between CYT and the buccal membrane. The solvent casting method was employed to prepare several thin films combining various excipients such as matrixing polymers, mucoadhesion agents, plasticizers and other compounds as humectants and sweeteners, component ratios and solvents. A total of 36 compositions was prepared and four of them emerged as the most promising in terms of aspect and flexibility. They all demonstrated homogeneity, thinness, low swelling degree, and controlled drug release according to the Power Law and Peppas-Sahlin mathematical models. Mainly, they proved able to interact with the ex vivo porcine buccal mucosa producing mucoadhesive effects, and act as potent permeation enhancers. In particular, Film B emerged as suitable as it produced a 10.6-fold Kp enhancement and a great Js value (52.33 µg/cm2·h-1), even when compared to highly concentrated CYT solutions.

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Bortezomib (BTZ) is a potent proteasome inhibitor currently being used to treat multiple myeloma. However, its high toxicity and resistance to therapy severely limit the treatment outcomes. Drug-membrane interactions have a crucial role in drugs' behavior in vivo, affecting their bioavailability and pharmacological activity. Additionally, drugs' toxicity often occurs due to their effects on the cell membranes. Therefore, studying BTZ's interactions with cell membranes may explain the limitations of its therapy. Due to the cell membranes' complexity, lipid vesicles were proposed here as biomembrane models, focusing on the membrane's main constituents. Two models with distinct composition and complexity were used, one composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and the other containing DMPC, cholesterol (Chol), and sphingomyelin (SM). BTZ's interactions with the models were evaluated regarding the drugs' lipophilicity, preferential location, and effects on the membrane's physical state. The studies were conducted at different pH values (7.4 and 6.5) to mimic the normal blood circulation and the intestinal environment, respectively. BTZ revealed a high affinity for the membranes, which proved to be dependent on the drug-ionization state and the membrane complexity. Furthermore, BTZ's interactions with the cell membranes was proven to induce changes in the membrane fluidity. This may be associated with its resistance to therapy, since the activity of efflux transmembrane proteins is dependent on the membrane's fluidity.

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The modified 1,2-benzothiazine analogues designed as new drug candidates and discussed in this paper are oxicam derivatives. Oxicams are a class of non-steroidal anti-inflammatory drugs (NSAIDs). Their biological target is cyclooxygenase (COX), a membrane protein associated with the phospholipid bilayer. In recent decades, it has been proven that the biological effect of NSAIDs may be closely related to their interaction at the level of the biological membrane. These processes are often complicated and the biological membranes themselves are very complex. Therefore, to study these mechanisms, simplified models of biological membranes are used. To characterize the interaction of six oxicam derivatives with DPPC, DMPC and EYPC, artificial models of biological membranes (multi-bilayers or liposomes), differential scanning calorimetry (DSC) and fluorescence spectroscopy techniques were applied. In spectroscopic measurements, two fluorescent probes (Laurdan and Prodan) localized in different membrane segments were used. All tested oxicam derivatives interacted with the lipid bilayers and may penetrate the artificial models of biological membranes. They intercalated into the lipid bilayers and were located in the vicinity of the polar/apolar membrane interface. Moreover, a good drug candidate should not only have high efficiency against a molecular target but also exhibit strictly defined ADMET parameters, therefore these activities of the studied compounds were also estimated.

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In this research, a new phospholipid based monolith was fabricated by in situ co-polymerization of 1-dodecanoyl-2-(11-methacrylamidoundecanoyl)-sn-glycero-3-phosphoethanolamine and ethylene dimethacrylate to mimick bio-membrane environment. Excellent physicochemical properties of this novel monolith that were achieved included column efficiency, stability, and permeability. Moreover, the biomimetic monolith showed outstanding separation capability for a series of intact proteins and small molecules. In particular, it exhibited good potential as an alternative to the commercial immobilized artificial membrane (IAM) column (IAM.PC.DD2) for studying drug-membrane interactions. This study not only enriched the types of IAM stationary phases, but also provided a simple model for the prediction of phosphatidylethanolamine related properties of drug candidates.

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In this research,a new phospholipid based monolith was fabricated by in situ co-polymerization of 1-dodecanoyl-2-(11-methacrylamidoundecanoyl)-sn-glycero-3-phosphoethanolamine and ethylene dimethacrylate to mimick bio-membrane environment.Excellent physicochemical properties of this novel monolith that were achieved included column efficiency,stability,and permeability.Moreover,the biomimetic monolith showed outstanding separation capability for a series of intact proteins and small molecules.In particular,it exhibited good potential as an alternative to the commercial immobilized artificial membrane(IAM)column(IAM.PC.DD2)for studying drug-membrane interactions.This study not only enriched the types of IAM stationary phases,but also provided a simple model for the prediction of phosphatidylethanolamine related properties of drug candidates.

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Camptothecin (CPT) is a potent anticancer drug, and its putative oral administration is envisioned although difficult due to physiological barriers that must be overcome. A comprehensive biophysical analysis of CPT interaction with biointerface models can be used to predict some pharmacokinetic issues after oral administration of this or other drugs. To that end, different models were used to mimic the phospholipid composition of normal, cancer, and blood-brain barrier endothelial cell membranes. The logD values obtained indicate that the drug is well distributed across membranes. CPT-membrane interaction studies also confirm the drug's location at the membrane cooperative and interfacial regions. The drug can also permeate membranes at more ordered phases by altering phospholipid packing. The similar logD values obtained in membrane models mimicking cancer or normal cells imply that CPT has limited selectivity to its target. Furthermore, CPT binds strongly to serum albumin, leaving only 8.05% of free drug available to be distributed to the tissues. The strong interaction with plasma proteins, allied to the large distribution (VDSS = 5.75 ± 0.932 L·Kg-1) and tendency to bioaccumulate in off-target tissues, were predicted to be pharmacokinetic issues of CPT, implying the need to develop drug delivery systems to improve its biodistribution.

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PURPOSE: AntiOxCIN3 is a novel mitochondriotropic antioxidant developed to minimize the effects of oxidative stress on neurodegenerative diseases. Prior to an investment in pre-clinical in vivo studies, it is important to apply in silico and biophysical cell-free in vitro studies to predict AntiOxCIN3 biodistribution profile, respecting the need to preserve animal health in accordance with the EU principles (Directive 2010/63/EU). Accordingly, we propose an innovative toolbox of biophysical studies and mimetic models of biological interfaces, such as nanosystems with different compositions mimicking distinct membrane barriers and human serum albumin (HSA). METHODS: Intestinal and cell membrane permeation of AntiOxCIN3 was predicted using derivative spectrophotometry. AntiOxCIN3 -HSA binding was evaluated by intrinsic fluorescence quenching, synchronous fluorescence, and dynamic/electrophoretic light scattering. Steady-state and time-resolved fluorescence quenching was used to predict AntiOxCIN3-membrane orientation. Fluorescence anisotropy, synchrotron small- and wide-angle X-ray scattering were used to predict lipid membrane biophysical impairment caused by AntiOxCIN3 distribution. RESULTS AND DISCUSSION: We found that AntiOxCIN3 has the potential to permeate the gastrointestinal tract. However, its biodistribution and elimination from the body might be affected by its affinity to HSA (>90%) and by its steady-state volume of distribution (VDSS =1.89± 0.48 L∙Kg-1). AntiOxCIN3 is expected to locate parallel to the membrane phospholipids, causing a bilayer stiffness effect. AntiOxCIN3 is also predicted to permeate through blood-brain barrier and reach its therapeutic target - the brain. CONCLUSION: Drug interactions with biological interfaces may be evaluated using membrane model systems and serum proteins. This knowledge is important for the characterization of drug partitioning, positioning and orientation of drugs in membranes, their effect on membrane biophysical properties and the study of serum protein binding. The analysis of these interactions makes it possible to collect valuable knowledge on the transport, distribution, accumulation and, eventually, therapeutic impact of drugs which may aid the drug development process.

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Pharmacological efficiency of active compounds is largely determined by their membrane permeability. Thus, identification of drug-membrane interactions seems to be a crucial element determining drug-like properties of chemical agents. Yet, knowledge of this issue is still lacking. Since chemoprevention based on natural compounds such as cinnamic acid (CinA), p-coumaric acid (p-CoA) and ferulic (FA) is becoming a strong trend in modern oncopharmacology, determination of physicochemical properties of these anticancer compounds is highly important. Here, electrophoretic light scattering and impedance spectroscopy were applied to study the effects of these phenolic acids on electrical properties of bilayers formed from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-diacyl-sn-glycero-3-phospho-l-serine (PS) or DOPC-PS mixture. After phenolic acid treatment, the negative charge of membranes increased in alkaline pH solutions, but not in acidic ones. The impedance data showed elevated values of both the electrical capacitance and the electrical resistance. We concluded that at acidic pH all tested compounds were able to solubilize into the membrane and permeate it. At neutral and alkaline pH, the CinA could be partially inserted into the bilayers, whereas p-CoA and FA could be anchored at the bilayer surface. Our results indicate that the electrochemical methods might be crucial for predicting pharmacological activity and bioavailability of phenolic acids.

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Fipronil is a widely used commercial insecticide whose action mechanism consists in blocking the influx of chloride ions through the γ-aminobutyric acid type A receptor (GABAA-R), an integral membrane protein. The present study investigates the interaction of fipronil with phospholipid Langmuir monolayers, in order to characterize the effects that its partition could exert on the physical properties of these model membranes. A combined experimental and molecular dynamics (MD) simulations approach was performed. MD simulations were conducted in such a way that they resemble an experimental compression isotherm of DPPC in the presence of fipronil in the aqueous subphase. Both the experimental and the simulated compression isotherm showed that the partition of fipronil between DPPC molecules induces an expansion of the monolayer. Experimental results also showed that fipronil can penetrate lipid monolayers even in condensed packing states. MD simulations showed that fipronil induces an ordering effect in the acyl chains of DPPC in the liquid-condensed phase. In addition, the simulations indicate that fipronil orients parallel to the plane of the monolayer and that it establishes hydrogen bonds with the glycerol region of DPPC. Free energy profiles of the partition of fipronil into the monolayers, obtained by means of umbrella sampling, indicated that its penetration is thermodynamically favorable, being the interphase between the glycerol region and the acyl chains of DPPC its most favorable location. Our results suggest that fipronil could modulate the supramolecular organization of biological membranes surrounding GABAA-R, contributing, at least in part, to its action mechanism.

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Levothyroxine (3,5,3',5'-tetraiodothyronine), which is a L-isomer of thyroxine T4 (L-T4), is a synthetic thyroid hormone that is biochemically and physiologically indistinguishable from endogenous T4. It is used as a thyroid hormone replacement drug to treat an underactive thyroid gland. The interaction of L-T4, with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) was studied in the presence (1 mol%, 3 mol%, 6 mol%, 9 mol%, 15 mol%, 24 mol% and 30 mol%) and absence of L-T4 by using two different non-invasive techniques; Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC). The results show that L-T4 does perturb the phase transition profile by either decreasing the main transition temperature (Tm) and enthalpy (ΔH) or increasing the width at half height (ΔT½). That means; it changes the physical properties of DPPC bilayers. Addition of L-T4 into pure DPPC liposomes shifts the phase transition to lower temperature, disorder the system in gel phase with opposite effect in liquid-crystalline phase and increases the dynamics of the system in both phases and also causes dehydration of the groups of lipids and the water molecules around.

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Agents capable of scavenging ROS have attracted attention recently because of their potential use as antioxidative agents. Amifostine, a ROS scavenger, has the potential to be used as an antioxidant in therapeutic applications. In this study, the effect of amifostine on neutral zwitterionic dipalmitoylphosphatidylcholine (DPPC) and anionic dipalmitoylphosphatidylglycerol (DPPG) model membranes' structure and dynamics is aimed to be examined by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Our results revealed that amifostine at concentrations used (1-24 mol%) does not induce any important alteration in the shape of phase transition curve and phase transition temperature in the DPPC and DPPG membranes. High concentrations of amifostine slightly increased the acyl chain flexibility of DPPC membranes in the liquid crystalline phase and DPPG membranes in the gel phase. A lessening in the dynamics of DPPC liposomes was observed for all concentrations of amifostine in both phases but slight dual effect was observed only in the gel phase as a decrease in dynamics at low concentrations and an increase at higher concentrations of amifostine in DPPG liposomes. Additionally, strong hydrogen bonding was observed for both CO and PO2- groups in case of DPPC and for PO2- groups in case of DPPG. Dehydration around the CO regions occurred in case of DPPG. Accordingly, amifostine is proposed to be interacting strongly with zwitterionic and negatively charged membrane head groups and glycerol backbone in all concentrations and because of this interaction it causes some changes in lipid order and dynamics especially at high concentrations.

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Individual and joint action of two water-soluble drugs, DMSO and tilorone, on model l-α-dipalmitoylphosphatidylcholine (DPPC) membranes were studied in equilibrium and kinetic regimes by differential scanning calorimetry (DSC). For equilibrium experiments, the drugs were introduced during preparation of the model membrane. In kinetic studies, one of the drugs was added to the DPPC membrane already containing the other drug, and the effects of drug-membrane interactions were monitored in real-time regime. It was found that tilorone and DMSO had opposite effects on the membrane melting temperature, which were non-additive under joint introduction of these drugs. Analysis of kinetics of DSC profiles under drugs introduction allowed us to discriminate two processes in drug-membrane interactions with different characteristic times, i.e., drug sorption onto the membrane (minutes) and drug diffusion through stacks of lipid bilayers (hours). It was established that 0.1 mol% DMSO effectively enhanced membrane penetration for tilorone with the rate of tilorone diffusion being dependent upon the scheme of drugs administration. A model was proposed describing how sorption of a dopant onto lipid membrane could affect the membrane permeability for other dopants. Conditions were determined for enhancement of membrane permeability, as it was observed for DPPC/DMSO/tilorone system.

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Budesonide (BUD), a poorly soluble anti-inflammatory drug, is used to treat patients suffering from asthma and COPD (Chronic Obstructive Pulmonary Disease). Hydroxypropyl-ß-cyclodextrin (HPßCD), a biocompatible cyclodextrin known to interact with cholesterol, is used as a drug-solubilizing agent in pharmaceutical formulations. Budesonide administered as an inclusion complex within HPßCD (BUD:HPßCD) required a quarter of the nominal dose of the suspension formulation and significantly reduced neutrophil-induced inflammation in a COPD mouse model exceeding the effect of each molecule administered individually. This suggests the role of lipid domains enriched in cholesterol for inflammatory signaling activation. In this context, we investigated the effect of BUD:HPßCD on the biophysical properties of membrane lipids. On cellular models (A549, lung epithelial cells), BUD:HPßCD extracted cholesterol similarly to HPßCD. On large unilamellar vesicles (LUVs), by using the fluorescent probes diphenylhexatriene (DPH) and calcein, we demonstrated an increase in membrane fluidity and permeability induced by BUD:HPßCD in vesicles containing cholesterol. On giant unilamellar vesicles (GUVs) and lipid monolayers, BUD:HPßCD induced the disruption of cholesterol-enriched raft-like liquid ordered domains as well as changes in lipid packing and lipid desorption from the cholesterol monolayers, respectively. Except for membrane fluidity, all these effects were enhanced when HPßCD was complexed with budesonide as compared with HPßCD. Since cholesterol-enriched domains have been linked to membrane signaling including pathways involved in inflammation processes, we hypothesized the effects of BUD:HPßCD could be partly mediated by changes in the biophysical properties of cholesterol-enriched domains.

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