We have previously reported preferential release of polyunsaturated FAs during hydrolysis of lipoprotein phosphatidylcholine (PtdCho) by group X secretory phospholipase A2 (sPLA2) and preferential release of oligounsaturated FAs during hydrolysis of lipoprotein PtdCho by group V sPLA2, but the mechanism of this selectivity has remained unknown. We now show that the rate and specificity of hydrolysis are affected by relative increases in endogenous SM and free cholesterol (FC) during the lipase digestion. The highest preference for arachidonate release from LDL and HDL by group X sPLA2 was observed for residual SM/PtdCho molar ratio of 1.2 and 0.4, compared with the respective starting ratios of 0.4 and 0.2, as measured by liquid chromatography/electrospray ionization-mass spectrometry. Group V sPLA2 showed preferential release of linoleate from LDL and HDL at SM/PtdCho ratio 1.5 and 0.6, respectively. We have attributed the change in FA specificity to segregation of molecular species of PtdCho and of sPLA2s between disordered and ordered SM/FC/PtdCho lipid phases. The increases in SM and FC during digestion with group IIA sPLA2 were more limited, and a preferential hydrolysis of any FAs was not observed. The significance of SM and FC SM and FC accumulation during sPLA2 hydrolysis of lipoprotein PtdCho has been previously overlooked.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1194/jlr.M800167-JLR200 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Adsorption adaptive response exposed to algal organic matter: correlation to the characteristics of granular activated carbon.
Environ Technol
January 2025
College of Architecture & Civil Engineering, Beijing University of Technology, Beijing, People's Republic of China.
The release of algal organic matter (AOM) during seasonal algal blooms increases the complexity and heterogeneity of natural organic matter (NOM) in water sources, altering its hydrophilic-hydrophobic balance and posing significant challenges to conventional water treatment processes. This study aims to verify whether the (Granular activated carbon) GAC selected for the adsorption of NOM in sand filtration effluent can adapt to water quality fluctuations caused by AOM release, and identify the criteria influencing GAC adsorption performance. Results indicated that external surface area, mesopore volume, pore size and surface functional groups were key indicators of GAC adsorption performance.
View Article and Find Full Text PDFReceptors for the vasoactive adipokine apelin, termed APJ receptors, are G-protein-coupled receptors and are widely expressed throughout the cardiovascular system. APJ receptors can also signal via G-protein-independent pathways, including G-protein-coupled-receptor kinase 2 (GRK2), which inhibits nitric oxide synthase (eNOS) activity and nitric oxide (NO) production in endothelial cells. Apelin causes endothelium-dependent, NO-mediated relaxation of coronary arteries from normotensive animals, but the effects of activating APJ receptor signaling pathways in hypertensive coronary arteries are largely unknown.
View Article and Find Full Text PDFHow cells align to structured collagen fibrils: a hybrid cellular Potts and molecular dynamics model with dynamic mechanosensitive focal adhesions.
Front Cell Dev Biol
January 2025
Mathematical Institute, Faculty of Science, Leiden University, Leiden, Netherlands.
Many mammalian cells, including endothelial cells and fibroblasts, align and elongate along the orientation of extracellular matrix (ECM) fibers in a gel when cultured . During cell elongation, clusters of focal adhesions (FAs) form near the poles of the elongating cells. FAs are mechanosensitive clusters of adhesions that grow under mechanical tension exerted by the cells' pulling on the ECM and shrink when the tension is released.
View Article and Find Full Text PDFCore-Satellite Nanoassembly Overcomes Spatial Heterogeneity of Dendric Cell Distribution in Pancreatic Tumors for Effective Chemoimmunotherapy.
ACS Nano
January 2025
Nanomedicine Research Center, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China.
Pancreatic cancer therapies such as chemotherapy and immunotherapy are hindered by the dense extracellular matrix known as physical barriers, leading to heterogeneity impeding the effective penetration of chemotherapeutic agents and activation of antitumor immune responses. To address this challenge, we developed a hybrid nanoassembly with a distinct core-satellite-like heterostructure, PLAF@P/T-PD, which is responsive to both internal pH/redox and external ultrasound stimulations. This heterostructural nanoassembly features a polymersome core encapsulating an ultrasound contrast agent perfluoropentane and a chemotherapeutic agent Taxol (PLAF@P/T) electrostatically coated with satellite-like polyplexes carrying an immune agonist dsDNA (PD), which brings about synergistic functions inside the pancreatic tumor.
View Article and Find Full Text PDFHydrolyzing collagen by extracellular protease Hap of Aeromonas salmonicida: Turning chicken by-products into bioactive resources.
Food Chem
January 2025
State Key Laboratory of Meat Quality Control and Cultured Meat Development, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China. Electronic address:
Collagen-rich meat processing by-products have potential utilization value. Extracellular protease Hap from meat-borne Aeromonas salmonicida has been identified as an ideal protease for hydrolyzing collagen. Here, to explore the possible application of Hap for giving chicken by-products a high added value, the hydrolysis ability and mechanism were investigated.
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!