Disease relevance of Laurdan

• In these samples, Laurdan could be used as a simple tool for infertility assessment [1].
• GPS, the slope of laurdan generalized polarization spectra, in the study of phospholipid lateral organization and Escherichia coli lipid phases [2].
• Use of the fluorescent probe Laurdan to investigate structural organization of the vesicular stomatitis virus (VSV) membrane [3].

High impact information on Laurdan

• The fluorescent probe Laurdan and two-photon microscopy revealed that focal adhesions are highly ordered; in fact, they are more ordered than caveolae or domains that stain with cholera toxin subunit B (CtxB) [4].
• To address whether these rearrangements involve alteration in the structure of the plasma membrane bilayer, we used the fluorescent probe Laurdan to visualize its lipid order [5].
• Furthermore, by using fluorescence recovery after photobleaching studies of domain connectivity and the generalized polarization spectra of Laurdan, we demonstrate that FAPP2 depletion impairs the formation of condensed apical membrane domains [6].
• Experimental approaches using Laurdan extrinsic fluorescence and Förster-type resonance energy transfer (FRET) that led to the characterization of the polarity and molecular dynamics of the liquid-ordered phase AChR-vicinal lipids and the bulk membrane lipids, and the asymmetry of the AChR-rich membrane are reviewed first [7].
• Optical microspectrophotometry of Laurdan-labeled neutrophils revealed a large blue shift at lamellipodia relative to cell bodies [8].

Chemical compound and disease context of Laurdan

• Idiopathic infertility: susceptibility of spermatozoa to in-vitro capacitation, in the presence and the absence of palmitylethanolamide (a homologue of anandamide), is strongly correlated with membrane polarity studied by Laurdan fluorescence [9].

Biological context of Laurdan

• The changes in the efficiency of the Förster energy transfer from the protein to Laurdan brought about by addition of FFA, together with the distances involved in this process, indicate that all FFA studied share a common site at the lipid-protein interface [10].
• Membrane aging during cell growth ascertained by Laurdan generalized polarization [11].
• The generalized polarization (GP) of Laurdan-labeled cells contains useful information about membrane fluidity and polarity [12].
• In the initial phase, <50 ps, the redshift in the spectral mass center is much faster for laurdan excited at the blue edge (350 nm), whereas at longer time intervals, similar kinetics is observed upon excitation at either blue or red edge (400 nm) [13].
• We tested the susceptibility to oxidative stress in vitro, the fatty acid content, the fluidity using 2-dimethylamino-(6-lauroyl)-naphthalene (Laurdan) and 1,6-difenil-1,3,5-esatriene (DPH) probes [14].

Anatomical context of Laurdan

• In all cases redshifts of 50 to 60 nm were observed as a function of temperature in the spectral emission maximum of laurdan embedded in these membranes [15].
• Visualizing membrane microdomains by Laurdan 2-photon microscopy (Review) [16].
• Two-photon excitation microscopy shows coexisting regions of different generalized polarization (GP) in phospholipid vesicles, in red blood cells, in a renal tubular cell line, and in purified renal brushborder and basolateral membranes labeled with the fluorescent probe laurdan [17].
• Microvesicle membranes appeared more ordered than native erythrocytes and similar to ionophore-treated cells based on laurdan emission [18].
• The fluorescent probe Laurdan, localized only within the plasma membrane of spermatozoa, is particularly useful to evaluate bilayer polarity in this part of the cell [9].

Associations of Laurdan with other chemical compounds

• Previous fluorescence and infrared data indicated that membrane perturbation caused by the probes increases in the order: Laurdan > Prodan > Acdan [19].
• Cholesterol depletion also resulted in a significant increase in membrane lipid fluidity and alterations in lipid microdomains as determined by laurdan fluorescence spectroscopy and imaging [20].
• A still unexploited property of laurdan, namely its ability to act as a fluorescence energy transfer acceptor from tryptophan emission, has been used to measure properties of the protein-vicinal lipid [15].
• Absorption, steady-state, and time-resolved fluorescence measurements have been performed on laurdan dissolved either in white viscous apolar solvents or in ethanol as a function of temperature [21].
• We studied the dipolar relaxation of the surfactant-water interface in reverse micelles of AOT-water in isooctane in the nanosecond and subnanosecond time ranges by incorporating the amphipathic solvatochromic fluorescent probes LAURDAN and TOE [22].

Gene context of Laurdan

• The generalized polarization of Laurdan increased with increasing cholesterol, showing an abrupt modification at the native cholesterol content [23].
• RESULT: Our results show a red shift of the fluorescence excitation and emission spectra of Laurdan in PMN from the PCD group with respect to the control group [24].
• No modifications of apoprotein structure and physico-chemical properties were observed in Hcy-LDL with respect to control LDL (c-LDL), as evaluated using the intrinsic fluorescence of tryptophan and the probe Laurdan incorporated in lipoproteins [25].
• Contrarily, the Laurdan molecule was not squeezed out from the glycerol backbone region because the long acyl chain of Laurdan serves as an anchor in the hydrophobic core of bilayer [26].

Analytical, diagnostic and therapeutic context of Laurdan

• Mitochondrial creatine kinase binding to phospholipids decreases fluidity of membranes and promotes new lipid-induced beta structures as monitored by red edge excitation shift, laurdan fluorescence, and FTIR [27].
• Finally, titration curves of enflurane effect in the mixed lipidic phase has been obtained by using the fluorescent lipid probe Laurdan [28].
• Specifically, laurdan anisotropy and emission spectra were obtained from native erythrocytes before and after treatment with calcium ionophore and from the microvesicles (known to be enriched in liquid ordered domains) shed from the cells during calcium entry [18].
• Time-resolved fluorescence emission spectra of Laurdan in phospholipid vesicles by multifrequency phase and modulation fluorometry [29].
• Perturbation of the chain melting transition of DPPC by galactose, agarose and Laurdan as determined by differential scanning calorimetry [30].

References