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Herbal Product Development and Characteristics
Published in Anil K. Sharma, Raj K. Keservani, Surya Prakash Gautam, Herbal Product Development, 2020
Mirian Pateiro, Rubén Domínguez, Predrag Putnik, Danijela Bursać Kovačević, Francisco J. Barba, Paulo S. E. Munekata, Elena Movilla Fierro, José M. Lorenzo
The biomembranes are cellular structures that surround living organisms. They are formed by a double lipid layer, which confers with one of its most important functions, as regulation of the entry and exit of macromolecules, whether or not this is intracellular or extracellular delivery. In addition, they are also characterized by possessing capacity for selective permeability. Biomembranes also contain three types of proteins, such as ion channels, receptors, and transporters which allow the exchange of substances with other cells or tissues. The presence of polyphenols can modify activity of these proteins, what could change the interactions with phospholipids (Figure 8.3b) (Wink, 2015).
Features of Lipid Metabolism in Diabetes Mellitus and Ischemic Heart Disease
Published in E.I. Sokolov, Obesity and Diabetes Mellitus, 2020
Cholesterol and phospholipids are the main components of biomembranes. The former, responsible for 23% of the total mass of a membrane’s lipids, is a very important regulator of the membrane in an erythrocyte. It acts like a shuttle transferring glucose, amino acids, and salts. Cholesterol is what ensures the difference in the physicochemical state of a membrane, and it is in two forms — free and esterified. If an erythrocyte membrane is too dense, the cholesterol “liquefies” it, as it were; conversely, if a membrane is too “liquid”, the cholesterol compacts it. Consequently, the state of aggregation of the membrane of erythrocytes is ensured to a considerable extent with the aid of cholesterol. There is a constant exchange of cholesterol between the erythrocytes and blood plasma [282, 362, 378, 417].
Tracking and Imaging
Published in Qiu-Xing Jiang, New Techniques for Studying Biomembranes, 2020
Biomembrane is a fundamental component of most living systems. It is the structure separating the exterior regions of the intracellular components from the extracellular environment, yet selectively connecting the cell to the environment with materials and chemical signals. To understand the structure and function of biomembranes, identification of components, mapping their distribution and monitoring the related biological process is helpful and possible by SERS. Raman spectra are generated in response to molecular vibration due to polarizability change of molecules which could provide a wealth of information of the structures, enabling label-free recognition of targets. Compared to infrared spectroscopy, the Raman signal is not affected by the presence of water, facilitating characterization of biomembranes in solution phase. However, due to the limited Raman scattering cross section, the intensity of Raman spectrum is usually weak, thus influencing its signal. Surface-enhanced Raman spectroscopy (SERS) could greatly enhance the intensity of the spectrum with an average enhancement factor of ~106,(1) and perhaps as high as 1014–1015,(2) as claimed in some reports, facilitating detection at lower concentrations and from finer structure changes.
Biotherapeutic effect of cell-penetrating peptides against microbial agents: a review
Published in Tissue Barriers, 2022
Idris Zubairu Sadiq, Aliyu Muhammad, Sanusi Bello Mada, Bashiru Ibrahim, Umar Aliyu Umar
Cell-Penetrating Peptides also referred to as protein transduction domains, membrane transduction peptides, and Trojan peptides encompass a group of distinctive peptides, which span in length to approximately 5–30 amino acids capable of crossing the cellular plasma membranes.1 These peptides have ascended as a powerful therapeutic alternative to small molecules and transporting other cargoes and targeting intracellular proteins, and unlike small molecules, providing tremendous advantages in terms of drug delivery as well as other possible therapeutic benefits.2,3 Typically, the amino acid composition of CPP consists of a relatively high abundance of positively charged amino acids, for example, lysine and arginine, or may simply contain alternating sequences containing charged polar amino acid and nonpolar, hydrophobic amino acid patterns.4 As the CPPs possessed the ability to cross-cellular membranes, these peptides also allow a wide range of therapeutic agents to enter cellular compartments without disrupting biomembranes.5 One great challenge often faced in many human diseases is the cell and tissue barriers, preventing therapeutics from reaching their specific intracellular targets.6,7
Facile L-Glutamine delivery to erythrocytes via DOPC-DPPG mixed liposomes
Published in Journal of Liposome Research, 2021
In summary, preventing cell dehydration is a critical step in the case of SCD. As stated in the literature, there is a need for a new drug delivery system that will be an alternative to the methods currently used for this purpose and that can function more effectively. We plan to use liposomes as the drug transport system in this study. Liposomes have more often been preferred for drug delivery due to their advantageous properties in recent years (Irie et al.2003, Fricker et al.2010, Guan et al.2011, Mishra et al.2011, Niu et al.2011). Owing to their amphiphilic structure, generally, liposomes formed from one or more phospholipids have the advantage of encapsulating or carrying hydrophilic and hydrophobic drug molecules in their structures at the same time (Moen et al.2009). As they are composed with both biodegradable and biocompatible lipids, they can mimic biomembranes (Zasadzinski et al. 2011).
A physico-chemical study on amphiphilic cyclodextrin/liposomes nanoassemblies with drug carrier potential
Published in Journal of Liposome Research, 2020
T. Musumeci, A. Bonaccorso, F. De Gaetano, K. L. Larsen, R. Pignatello, A. Mazzaglia, G. Puglisi, C. A. Ventura
Liposomes used as biomembrane models were prepared using the TLE method. Briefly, DPPC (10 mg) was dissolved in chloroform in a pyrex glass test-tube. The organic solvent was removed at 30.0 ± 0.1 °C on nitrogen stream rotavapor (Rotavapor-M Büchi HB-140, Flawil, Switzerland) until the lipids were dried and distributed as a thin film on the wall of the tube. Any possible trace of organic solvent was eliminated by 24 h of storage at 40.0 ± 0.1 °C under high vacuum (Buchi T-50, Flawil, Switzerland). The films were hydrated by adding 400 μl of isotonic PBS (pH 7.4). The tube was alternatively vortexed (Heidolph REAX 2000, Schwabach, Germany) and warmed in a water bath at 55 °C for 3 min twice. The temperature was kept higher than that of DPPC gel-liquid crystal phase transition (42 °C) to allow full hydration of the phospholipid.