AuthorsHara T, Hirasawa A, Sun Q, Koshimizu TA, Itsubo C, Sadakane K, Awaji T, Tsujimoto G,
JournalMol Pharmacol
PubMed ID18927207
'GPR40 is a G protein-coupled receptor (GPCR) whose endogenous ligands have recently been identified as medium- and long-chain free fatty acids (FFAs), and it is thought to play an important role in insulin release. Despite recent research efforts, much still remains unclear in our understanding of its pharmacology, mainly because ... More
Genetic analysis of digestive physiology using fluorescent phospholipid reporters.
AuthorsFarber SA, Pack M, Ho SY, Johnson ID, Wagner DS, Dosch R, Mullins MC, Hendrickson HS, Hendrickson EK, Halpern ME
JournalScience
PubMed ID11359013
'Zebrafish are a valuable model for mammalian lipid metabolism; larvae process lipids similarly through the intestine and hepatobiliary system and respond to drugs that block cholesterol synthesis in humans. After ingestion of fluorescently quenched phospholipids, endogenous lipase activity and rapid transport of cleavage products results in intense gall bladder fluorescence. ... More
A novel fluorogenic substrate for the measurement of endothelial lipase activity.
'Endothelial lipase (EL) is a phospholipase A1 (PLA1) enzyme that hydrolyzes phospholipids at the sn-1 position to produce lysophospholipids and free fatty acids. Measurement of the PLA1 activity of EL is usually accomplished by the use of substrates that are also hydrolyzed by lipases in other subfamilies such as PLA2 ... More
Effects of the glucosphingolipid synthesis inhibitor, PDMP, on lysosomes in cultured cells.
AuthorsRosenwald AG, Pagano RE
JournalJ Lipid Res
PubMed ID7964184
'The glucosphingolipid synthesis inhibitor, 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) has a wide range of effects on cell physiology and morphology. Here, we studied the effects of high concentrations of PDMP on cells in culture and found that fluorescent analogs of PDMP targeted to the lysosomes of Chinese hamster ovary (CHO) cells. Overnight incubation ... More
A HPLC-fluorescence detection method for determination of phosphatidic acid phosphohydrolase activity: application in human myocardium.
AuthorsBurgdorf C, Prey A, Richardt G, Kurz T,
JournalAnal Biochem
PubMed ID18023403
Phosphatidic acid phosphohydrolase (PAP) catalyzes the dephosphorylation of phosphatidic acid (PA) to diacylglycerol, the second messenger responsible for activation of protein kinase C. Despite the crucial role of PAP lipid signaling, there are no data on PAP signaling function in the human heart. Here we present a nonradioactive assay for ... More
Penetration and distribution of three lipophilic probes in vitro in human skin focusing on the hair follicle.
AuthorsGrams YY, Bouwstra JA
JournalJ Control Release
PubMed ID12363451
Fluorescent model substances of increasing lipophilicity (Oregon Green) 488, Bodipy, FL C5 and Bodipy 564/570 C5) were selected to enable the visualization in the skin using confocal laser scanning microscopy. After measuring the penetration for 18 h, the nonfixed human scalp skin was imaged from the bottom parallel to the ... More
On-line visualization of dye diffusion in fresh unfixed human skin.
AuthorsGrams YY, Whitehead L, Cornwell P, Bouwstra JA
JournalPharm Res
PubMed ID15180345
PURPOSE: The purpose of the current study was to develop a new method to examine the diffusion in fresh unfixed human skin on-line. METHODS: Full thickness skin samples were cut perpendicular to the skin surface (cutting plane facing upwards) with a new cutting device forming part of the final diffusion ... More
Permeant lipophilicity and vehicle composition influence accumulation of dyes in hair follicles of human skin.
In skin and hair research drug targeting to the hair follicle is of great interest. Therefore the influence of permeant lipophilicity and vehicle composition on local accumulation has been examined using confocal laser scanning microscopy (CLSM). Formulations saturated with either Oregon Green 488, Bodipy FL C(5) or Bodipy 564/570 C(5) ... More
Intramolecularly quenched BODIPY-labeled phospholipid analogs in phospholipase A(2) and platelet-activating factor acetylhydrolase assays and in vivo fluorescence imaging.
AuthorsHendrickson HS, Hendrickson EK, Johnson ID, Farber SA
JournalAnal Biochem
PubMed ID10585741
Phospholipase substrate analogs containing both a fluorescent BODIPY group and a quenching 2,4-dinitrophenyl (DNP) group were synthesized. They showed little fluorescence, but upon hydrolysis became fluorescent as the quenching group was removed. Two substrates were phosphatidylethanolamine analogs with a BODIPY-pentanoyl group at the sn-2 position and DNP linked to the ... More
Separation of phospholipids in microfluidic chip device: application to high-throughput screening assays for lipid-modifying enzymes.
AuthorsLin S, Fischl AS, Bi X, Parce W
JournalAnal Biochem
PubMed ID12633607
Phospholipid molecules such as ceramide and phosphoinositides play crucial roles in signal transduction pathways. Lipid-modifying enzymes including sphingomyelinase and phosphoinositide kinases regulate the generation and degradation of these lipid-signaling molecules and are important therapeutic targets in drug discovery. We now report a sensitive and convenient method to separate these lipids ... More
Effects of a sphingolipid synthesis inhibitor on membrane transport through the secretory pathway.
AuthorsRosenwald AG, Machamer CE, Pagano RE
JournalBiochemistry
PubMed ID1567816
We investigated the effects of an inhibitor of sphingolipid biosynthesis, 1-phenyl-2-(decanoyl-amino)-3-morpholino-1-propanol (PDMP), on cells in culture. Two Golgi-associated enzymes were affected by incubation of cells with PDMP. The synthesis of glucosylceramide was inhibited at low concentrations of PDMP (2.5-10 microM), and in the presence of higher concentrations (greater than or ... More
Dimers of dipyrrometheneboron difluoride (BODIPY) with light spectroscopic applications in chemistry and biology.
AuthorsBergström F, Mikhalyov I, Hägglöf P, Wortmann R, Ny T, Johansson LB
JournalJ Am Chem Soc
PubMed ID11782171
A ground-state dimer (denoted D(I)) exhibiting a strong absorption maximum at 477 nm (epsilon = 97 000 M(-1)cm(-1)) can form between adjacent BODIPY groups attached to mutant forms of the protein, plasminogen activator inhibitor type 1 (PAI-1). No fluorescence from excited D(I) was detected. A locally high concentration of BODIPY ... More
Characterization of cholesterol-sphingomyelin domains and their dynamics in bilayer membranes.
AuthorsSamsonov AV, Mihalyov I, Cohen FS
JournalBiophys J
PubMed ID11509362
Lipids segregate with each other into small domains in biological membranes, which can facilitate the associations of particular proteins. The segregation of cholesterol and sphingomyelin (SPM) into domains known as rafts is thought to be especially important. The formation of rafts was studied by using planar bilayer membranes that contained ... More
Angiopoietin-2-integrin α5β1 signaling enhances vascular fatty acid transport and prevents ectopic lipid-induced insulin resistance.
Authors
JournalNat Commun
PubMed ID32532986
Structure/function relationships of adipose phospholipase A2 containing a cys-his-his catalytic triad.
Authors
JournalJ Biol Chem
PubMed ID22923616
Fluorometric High-Throughput Screening Assay for Secreted Phospholipases A2 Using Phospholipid Vesicles.
Authors
JournalJ Biomol Screen
PubMed ID27146384
A branched-chain amino acid metabolite drives vascular fatty acid transport and causes insulin resistance.