Incubation of Micrococcus lysodeikticus protoplasts with phosphatidylcholine liposomes and rat liver exchange proteins (pH 5.1 supernatant fraction) resulted in replacement of about one half of the bacterial total phospholipids by phosphatidylcholine. Protoplasts modified by phosphatidylcholine showed a decreased rate of oxidation of exogenous substrates (NADH, malate) and decreased ferricyanide reductase activity as compared to the initial protoplasts. At the same time incorporation of phosphatidylcholine had no influence on the level of endogeneous respiration. Protoplasts modified by phosphatidylcholine were osmotically more stable than the initial protoplasts. After osmotic lysis of the phosphatidylcholine protoplasts their NADH (malate) oxidase and ferricyanide reductase activities were restored. Incorporation of phosphatidylcholine into membrane ghosts, obtained by osmotic rupture of the initial protoplasts had only small if any effect on the malate and NADH oxidase and dehydrogenase activities. It is concluded that phosphatidylcholine in incorporated predominantly into the outer part of cytoplasmic membrane and that proteinmediated transfer of phosphatidylcholine results in restoration of the permeability barrier due to repair of local defects in the initial protoplast membrane.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1432-1033.1978.tb12609.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Biomimetic exosome harnessing exosomal lipidomics and functional proteins for PEDF-pDNA delivery in high altitude pulmonary edema intervention.
J Control Release
January 2025
School of Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu Province, China. Electronic address:
In the realm of gene therapy, given the exceptional performance of native exosomes, researchers have redirected their innovative focus towards exosome-mimetic nanovesicles (EMNs); however, the current design of most EMNs relies heavily on native cells or their components, inevitably introducing inter-batch variability issues and posing significant challenges for quality control. To overcome the excessive reliance on native cellular components, this study adopts a unique approach by precisely mimicking the lipid composition of exosomes and innovatively incorporating histone components to recapitulate the gene transfer characteristics of exosomes. We selected sphingomyelin (SM), phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylethanolamine (PE), and cholesterol as the lipid components, and employed the double emulsion method to prepare biomimetic exosomes carrying histone A and PEDF-DNA plasmids (His-pDNA@EMNs).
View Article and Find Full Text PDFOptimizing hydrophilic drug incorporation into SEDDS using dry reverse micelles: a comparative study of preparation methods.
Drug Deliv Transl Res
January 2025
Thiomatrix Forschungs- und Beratungs GmbH, Trientlgasse 65, 6020, Innsbruck, Austria.
Aim: It was the aim of this study to compare two different dry reverse micelle (RM) preparation methods for the incorporation of hydrophilic drugs into oral self-emulsifying drug delivery systems (SEDDS).
Methods: Cationic ethacridine lactate, anionic fluorescein sodium salt and the antibiotic peptide bacitracin were solubilized in RM containing sodium docusate, soy phosphatidylcholine and sorbitan monooleate in highly lipophilic oils such as squalane. In the dry addition (DA) method, drugs were directly added to empty RM in their powder form.
Design, evaluation, and in vitro-in vivo correlation of self-nanoemulsifying drug delivery systems to improve the oral absorption of exenatide.
J Control Release
January 2025
Department of Pharmacy, University of Copenhagen, Universitetsparken 2, Copenhagen 2100, Denmark; Bioneer A/S, Kogle Allé 2, Hørsholm 2970, Denmark. Electronic address:
The ability to predict the absorption of exenatide (Ex), a GLP-1 analogue, after oral dosing to rats in self-nanoemulsifying drug delivery systems (SNEDDS), using in vitro methods, was assessed. Ex was complexed with soybean phosphatidylcholine (SPC) prior to loading into SNEDDS. A design of experiments (DoE) approach was employed to develop SNEDDS incorporating medium-chain triglycerides (MCT), medium-chain mono- and diglycerides (MGDG), Kolliphor® RH40, and monoacyl phosphatidylcholine.
View Article and Find Full Text PDFEnhanced Stability and In Vitro Biocompatibility of Chitosan-Coated Lipid Vesicles for Indomethacin Delivery.
Pharmaceutics
December 2024
Department of Pharmacology, Faculty of Medicine, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania.
Background: Lipid vesicles, especially those utilizing biocompatible materials like chitosan (CHIT), hold significant promise for enhancing the stability and release characteristics of drugs such as indomethacin (IND), effectively overcoming the drawbacks associated with conventional drug formulations.
Objectives: This study seeks to develop and characterize novel lipid vesicles composed of phosphatidylcholine and CHIT that encapsulate indomethacin (IND-ves), as well as to evaluate their in vitro hemocompatibility.
Methods: The systems encapsulating IND were prepared using a molecular droplet self-assembly technique, involving the dissolution of lipids, cholesterol, and indomethacin in ethanol, followed by sonication and the gradual incorporation of a CHIT solution to form stable vesicular structures.
Maternal Plasma Choline Levels Are Positively Correlated with Maternal and Placental Phospholipid-DHA Content in Females with Obesity Who Receive DHA Supplementation.
J Nutr
December 2024
Division of Reproductive Sciences, Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States; Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States. Electronic address:
Background: Pregnancies complicated by maternal obesity are characterized by metabolic differences affecting placental nutrient transport and fetal development. Docosahexaenoic acid (DHA) is critical for fetal brain development and is primarily incorporated into phosphatidylcholine (PC). Recent evidence suggests that choline may enhance PC-DHA synthesis; however, data on the impact of maternal plasma choline on placental phospholipid DHA content in females with obesity are limited.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!