Stigmasterol and its esters encapsulated in liposomes: Characterization, stability, and derivative formation.

Dipalmitoylphosphatidylcholine liposomes were encapsulated with free stigmasterol (ST), stigmasteryl myristate (ME), and stigmasteryl oleate (OE). Their quality was determined using TEM, FT-IR spectroscopy, zeta potential and hydrodynamic diameter. The prepared liposomes were heated at 60 and 180 °C.

Ethosomal Gel for Topical Administration of Dimethyl Fumarate in the Treatment of HSV-1 Infections.

The infections caused by the HSV-1 virus induce lesions on the lips, mouth, face, and eye. In this study, an ethosome gel loaded with dimethyl fumarate was investigated as a possible approach to treat HSV-1 infections. A formulative study was conducted, evaluating the effect of drug concentration on size distribution and dimensional stability of ethosomes by photon correlation spectroscopy.

Physicochemical Properties, Fatty Acid Composition, Volatile Compounds of Blueberries, Cranberries, Raspberries, and Cuckooflower Seeds Obtained Using Sonication Method.

Every year, thousands of tons of fruit seeds are discarded as agro-industrial by-products around the world. Fruit seeds are an excellent source of oils, monounsaturated fatty acids, and n-6 and n-3 polyunsaturated essential fatty acids. This study aimed to develop a novel technology for extracting active substances from selected seeds that were obtained after pressing fruit juices.

Influence of phenothiazine molecules on the interactions between positively charged poly-l-lysine and negatively charged DPPC/DPPG membranes.

Phenothiazines are very effective antipsychotic drugs, which also have anticancer and antimicrobial activities. Despite being used in human treatment, the molecular mechanism of the biological actions of these molecules is not yet understood in detail. The role of the interactions between phenothiazines and proteins or lipid membranes has been much discussed.

Effect of phenothiazine compounds on the secondary structure and fibrillogenesis of poly-l-lysine.

Phenothiazine molecules are effective and commonly used antipsychotic drugs, especially in the treatment of schizophrenia. However, they produce strong extrapyramidal side-effects manifested by drug-induced parkinsonism. Because Parkinson's disease as a neurodegenerative illness is associated with the formation of amyloid fibrils in neuronal cells, it is postulated that the development of phenothiazine-induced parkinsonism may be related to the phenothiazine-induced formation of fibrillar aggregates.

Resveratrol modulates fibrillogenesis in a poly‑l‑lysine peptide.

Resveratrol (Res) is an effective inhibitor of amyloid fibril formation and reduces neuron cell toxicity. The effect of Res on the fibrillogenesis of a polar polypeptide, poly‑l‑lysine (PLL), was studied by Fourier-transform infrared spectroscopy, vibrational circular dichroism and transmission electron microscopy. Res molecules exhibited strong and specific inhibition of β-sheet-rich fibrils formed by PLL.

Influence of resveratrol on interactions between negatively charged DPPC/DPPG membranes and positively charged poly-l-lysine.

Resveratrol (Res), a natural polyphenol present in different plants and vegetables, exhibits potential therapeutic activity with cardioprotective, antineurodegenerative, antioxidant, and antitumor action. In this study, the effect of Res on the mutual interactions between positively charged poly-l-lysine (PLL) and negatively charged dipalmitoylphosphatidylcholine/dipalmitoylphosphatidylglycerol (DPPC/DPPG) membranes was studied using Fourier-transform infrared (FTIR) spectroscopy supported by principal component analysis (PCA). The interactions between PLL and DPPC/DPPG membranes were strongly affected by the presence of Res molecules.

Ethanol- and trifluoroethanol-induced changes in phase states of DPPC membranes. Prodan emission-excitation fluorescence spectroscopy supported by PARAFAC analysis.

It has been shown that Prodan emission-excitation fluorescence spectroscopy supported by Parallel Factor (PARAFAC) analysis is a fast, simple and sensitive method used in the study of the phase transition from the noninterdigitated gel (L) state to the interdigitated gel (LI) phase, triggered by ethanol and 2,2,2-trifluoroethanol (TFE) molecules in dipalmitoylphosphatidylcholines (DPPC) membranes. The relative contribution of lipid phases with spectral characteristics of each pure phase component has been presented as a function of an increase in alcohol concentration. It has been stated that both alcohol molecules can induce a formation of the LI phase, but TFE is over six times stronger inducer of the interdigitated phase in DPPC membranes than ethanol molecules.

Interaction of anesthetic molecules with α-helix and polyproline II extended helix of long-chain poly-l-lysine.

The effect of halothane, enflurane, sevoflurane, and isoflurane molecules, as volatile anesthetics, on the α-helices and polyproline II extended helices (PPII) of long-chain poly-l-lysine (PLL) were studied using Fourier-transform infrared and vibrational circular dichroism spectroscopy. Uncharged and charged α-helices, as well as charged extended PPII helices, were subjected to anesthetic actions in solvents with different pD values or methanol to water ratios. A crucial factor responsible for hindering the anesthetic-PLL interactions is shown to be the ionization of amino groups of the PLL side chains.

Anesthetic-dependent changes in the chain-melting phase transition of DPPG liposomes studied using near-infrared spectroscopy supported by PCA.

The effect of inhalation anesthetics (enflurane, isoflurane, sevoflurane or halothane) on the lipid chain-melting phase transition of negatively charged phospholipid membranes was studied using near-infrared (NIR) spectroscopy supported by Principal Component Analysis (PCA). NIR spectra of anesthetics-mixed dipalmitoylphosphatidylglycerol (DPPG) membranes were recorded in a range of the first overtone of the symmetric and antisymmetric stretching vibrations of CH groups of lipid aliphatic chains as a function of increasing temperature. Anesthetic-dependent changes in the trans to gauche conformers ratio of CH groups in the hydrocarbon lipid chains were characterized in detail and compared with the zwitterionic lipid membranes, which were built of dipalmitoylphosphatidylcholine (DPPC) molecules.

The PPII-to-α-helix transition of poly-l-lysine in methanol/water solvent mixtures accompanied by fibrillar self-aggregation: An influence of fluphenazine molecules.

Fourier-transform infrared, vibrational circular dichroism spectroscopy and transmission electron microscopy are used to follow the structural changes of pure and fluphenazine (FPh)-mixed poly-l-lysine (PLL) triggered by variations of the methanol to water ratio in solvent mixtures. FPh molecules are used as an effective psychotic drug but with a strong Parkinson's-related side effect. To answer the question whether FPh molecules can modify the fibril development, the PLL polypeptide was used as a model of α-helix- and PPII-rich fibrils.

Alpha-helix to beta-sheet transition in long-chain poly-l-lysine: Formation of alpha-helical fibrils by poly-l-lysine.

The temperature-induced α-helix to β-sheet transition in long-chain poly-l-lysine (PLL), accompanied by the gauche-to-trans isomerization of CH groups in the hydrocarbon side chains of Lys amino acid residues, and formation of β-sheet as well as α-helix fibrillar aggregates of PLL have been studied using Fourier-transform infrared (FT-IR) and vibrational circular dichroism (VCD) spectroscopy, and transmission electron microscopy (TEM). In a low-temperature alkaline water solution or in a methanol-rich water mixture, the secondary structure of PLL is represented by α-helical conformations with unordered and gauche-rich hydrocarbon side chains. Under these conditions, PLL molecules aggregate into α-helical fibrils.

Laurdan emission study of the cholesterol-like effect of long-chain alkylresorcinols on the structure of dipalmitoylphosphocholine and sphingomyelin membranes.

Long-chain alkylresorcinols (ARs) are commonly found in plant and bacteria cells, and they exhibit a wide variety of biological effects, including antifungal, antitumor, and antiphrastic activities. The cholesterol (Chol)-like effect of ARs with hydrocarbon side-chain lengths ranging from C15 to C25 on the structure of pure and Chol-doped dipalmitoylphosphocholine (DPPC) and sphingomyelin (SM) membranes was investigated by Laurdan fluorescence spectroscopy. The Laurdan emission generalized polarization parameter was analyzed as a function of the temperature and excitation wavelength in DPPC (or SM)/Chol, DPPC (or SM)/AR, and DPPC/Chol/AR systems.

Fluphenazine: from an isolated molecule to its interaction with lipid bilayers.

Fluphenazine (FPh) belongs to the phenothiazine family of compounds and exhibits a wide variety of biological effects, including antimutagenic, proapoptotic, antiproliferative and anti-multidrug resistance (MDR) activities. The ability of FPh to interact with lipid membranes can have a significant impact on its biological activities. However, the mechanisms involved in the interaction of FPh with lipid membranes are poorly understood.

Phase separation in phosphatidylcholine membrane caused by the presence of a pyrimidine analogue of fluphenazine with high anti-multidrug-resistance activity.

Phenothiazine compounds are known as effective inhibitors of a multidrug resistance (MDR) of tumor cells to chemotherapeutic agents. This group consists of many important substances used in human medicine such as antipsychotic drugs in the case of fluphenazine (FPh) or chlorpromazine (CPZ). Fluphenazine was on the World Health Organization (WHO) list of Essential Medicines of 2009, and its new pyrimidine analog (FPh-prm) presented in this work has been documented to have a high anti-MDR activity.

Interaction of piperidin derivative of Mannich base with DPPC liposomes.

The long chain Mannich bases, especially with the piperidine and morpholine groups, display very promising antimicrobial activity. In order to extend our knowledge on their impact on biological systems, we examined the interactions of the 5-pentadecyl-2-((piperidin-1-yl)methyl)phenol (PPDP) with model lipid membrane by means of differential scanning calorimetry (DSC) and fluorescence measurements. The small unilamellar vesicles of dipalmitoylophosphatidylcholine (DPPC) with different piperidine Mannich base concentration were investigated as a function of the increase of temperature.

Chemical structure of phenothiazines and their biological activity.

Phenothiazines belong to the oldest, synthetic antipsychotic drugs, which do not have their precursor in the world of natural compounds. Apart from their fundamental neuroleptic action connected with the dopaminergic receptors blockade, phenothiazine derivatives also exert diverse biological activities, which account for their cancer chemopreventive-effect, as: calmodulin- and protein kinase C inhibitory-actions, anti-proliferative effect, inhibition of P-glycoprotein transport function and reversion of multidrug resistance. According to literature data on relations between chemical structure of phenothiazines and their biological effects, the main directions for further chemical modifications have been established.

New fluphenazine analogues as inhibitors of P-glycoprotein in human lymphocyte cultures.

Aim Of The Study: To evaluate the inhibitory effect of 17 new analogues of FPh on the Pgp transport function, by estimation of the rhodamine 123 (Rod-123) accumulation inside cultured lymphocytes.

Material And Methods: Lymphocyte were cultured in the presence of a lectin (PHA; 2%, v/v), incubated with benzo[α]pyrene (B[α]P; 7.5 µM, 48 h) to induce genotoxic damage and to increase Pgp expression in the cells.

Generalized solvent scales as a tool for investigating solvent dependence of spectroscopic and kinetic parameters. Application to fluorescent BODIPY dyes.

Two difluoroboron dipyrromethene (BODIPY) based fluorescent dyes - 4,4-difluoro-3-{2-[4-(dimethylamino)phenyl]ethenyl}-8-[4-(methoxycarbonyl)phenyl]-1,5,7-trimethyl-3a,4a-diaza-4-bora-s-indacene (1) and 4,4-difluoro-3-[2-(4-fluoro-3-hydroxyphenyl)ethenyl]-8-[4-(methoxycarbonyl)phenyl]-1,5,7-trimethyl-3a,4a-diaza-4-bora-s-indacene (3) - have been synthesized via condensation of p-N,N-dimethylaminobenzaldehyde and 4-fluoro-3-hydroxybenzaldehyde, respectively, with 4,4-difluoro-8-[4-(methoxycarbonyl)phenyl]-1,3,5,7-tetramethyl-3a,4a-diaza-4-bora-s-indacene (2). UV-vis spectrophotometry and steady-state and time-resolved fluorometry have been used to study the spectroscopic and photophysical characteristics of in various solvents. The multi-parameter Kamlet-Taft {pi*, alpha, beta} solvent scales and a new, generalized treatment of the solvent effect, proposed by Catalán (J.

Interactions of dihydrochloride fluphenazine with DPPC liposomes: ATR-IR and 31P NMR studies.

The influence of dihydrochloride fluphenazine (FPh) on the dipalmitoylphosphatidylcholine (DPPC) bilayer structure was investigated using ATR-IR and (31)P NMR methods. The ATR-IR results indicate an increase in conformational disorder in the hydrophobic part compared with pure DPPC liposomes and a decrease in temperature of the chain-melting phase transition in FPh/DPPC liposomes. These effects depended on the concentration of the drug in the DPPC bilayer.

Photophysics and stability of cyano-substituted boradiazaindacene dyes.

The solvatochromic photophysical properties of two fluorescent, cyano-substituted BODIPY dyes-8-(4-bromophenyl)-3,4,4,5-tetracyano-4-bora-3a,4a-diaza-s-indacene (4CN) and 8-(4-bromophenyl)-3,5-dicyano-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (2CN)-have been studied in various solvents by UV-vis spectrophotometry and steady-state and time-resolved fluorometry. These two BODIPY analogues have comparable photophysical properties, implying that displacement of F by CN at boron has a negligible effect. Both compounds have high fluorescence quantum yields Phi(f) (0.

The effect of 3-pentadecylphenol on DPPC bilayers ATR-IR and 31P NMR studies.

The influence of 3-pentadecylphenol (PDP) on the structure and physicochemical properties of the lipid bilayers of DPPC liposomes was studied using ATR-IR and (31)P NMR methods. On the basis of analysis of the bands assigned to the CH(2) stretching, CH(2) scissoring, C=O stretching, and PO(2)(-) stretching vibrations it was revealed that PDP influences both the hydrophobic and hydrophilic parts of the DPPC liposome bilayer. Analysis of the (31)P NMR line-shape indicated a lamellar to non-lamellar phase transition in PDP-doped DPPC dispersions.

A semisynthetic 5-n-alkylresorcinol derivative and its effect upon biomembrane properties.

MSAR (1-sulfate-3-myristoyl-5-pentadecylbenzene) is a semisynthetic derivative of 5-n-pentadecylresorcinol (C15:0). MSAR exhibits hemolytic activity against sheep erythrocytes with a EH50 value of (35 +/- 1.7) microM.