Stefanko A.,Max Planck Institute of Molecular Cell Biology and Genetics |
Thiede C.,TU Dresden |
Ehninger G.,TU Dresden |
Simons K.,Max Planck Institute of Molecular Cell Biology and Genetics |
And 3 more authors.
PLoS ONE | Year: 2017
The pathogenesis and progression of many tumors, including hematologic malignancies is highly dependent on enhanced lipogenesis. De novo fatty-acid synthesis permits accelerated proliferation of tumor cells by providing membrane components but these may also alter physicochemical properties of lipid bilayers, which can impact signaling or even increase drug resistance in cancer cells. Cancer type-specific lipid profiles would permit us to monitor and interpret actual effects of lipid changes, potential fingerprints of individual tumors to be explored as diagnostic markers. We have used the shotgun MS approach to identify lipid patterns in different types of acute myeloid leukemia (AML) patients that either show no karyotype change or belong to t(8;21) or inv16 types. Differences in lipidomes of t(8;21) and inv(16) patients, as compared to AML patients without karyotype change, presented mostly as substantial modulation of ceramide/sphingolipid synthesis. Furthermore, between the t(8;21) and all other patients we observed significant changes in physicochemical membrane properties. These were related to a marked alteration in lipid saturation levels. The discovered differences in lipid profiles of various AML types improve our understanding of the pathobiochemical pathways involved and may serve in the development of diagnostic tools. © 2017 Stefanko et al.
PubMed | Lipotype GmbH and University of Oslo
Type: Journal Article | Journal: Oncotarget | Year: 2016
2-hydroxyoleic acid (OHOA, Minerval) is an example of a substance used for membrane lipid therapy, where the cellular membranes rather than specific proteins constitute the therapeutical target. OHOA is thought to mediate its anti-tumor effect by affecting the biophysical properties of membranes, which leads to altered recruitment and activation of amphitropic proteins, altered cellular signaling, and eventual cell death. Little is known about the initial signaling events upon treatment with OHOA, and whether the altered membrane properties would have any impact on the dynamic intracellular transport system. In the present study we demonstrate that treatment with OHOA led to a rapid release of intracellular calcium and activation of multiple signaling pathways in HeLa cells, including the PI3K-AKT1-MTOR pathway and several MAP kinases, in a process independent of the EGFR. By lipidomics we confirmed that OHOA was incorporated into several lipid classes. Concomitantly, OHOA potently increased retrograde transport of the plant toxin ricin from endosomes to the Golgi and further to the endoplasmic reticulum. The OHOA-stimulated ricin transport seemed to require several amphitropic proteins, including Src, phospholipase C, protein kinase C, and also Ca2+/calmodulin. Interestingly, OHOA induced a slight increase in endosomal localization of the retromer component VPS35. Thus, our data show that addition of a lipid known to alter membrane properties not only affects signaling, but also intracellular transport.
PubMed | Lipotype GmbH, University of Texas Health Science Center at Houston and Rice University
Type: Journal Article | Journal: Biophysical journal | Year: 2016
The plasma membrane (PM) serves as the functional interface between a cell and its environment, hosting extracellular signal transduction and nutrient transport among a variety of other processes. To support this extensive functionality, PMs are organized into lateral domains, including ordered, lipid-driven assemblies termed lipid rafts. Although the general requirements for ordered domain formation are well established, how these domains are regulated by cell-endogenous mechanisms or exogenous perturbations has not been widely addressed. In this context, an intriguing possibility is that dietary fats can incorporate into membrane lipids to regulate the properties and physiology of raft domains. Here, we investigate the effects of polyunsaturated fats on the organization of membrane domains across a spectrum of membrane models, including computer simulations, synthetic lipid membranes, and intact PMs isolated from mammalian cells. We observe that the -3 polyunsaturated fatty acid docosahexaenoic acid is robustly incorporated into membrane lipids, and this incorporation leads to significant remodeling of the PM lipidome. Across model systems, docosahexaenoic acid-containing lipids enhance the stability of ordered raft domains by increasing the order difference between them and coexisting nonraft domains. The relationship between interdomain order disparity and the stability of phase separation holds for a spectrum of different perturbations, including manipulation of cholesterol levels and high concentrations of exogenous amphiphiles, suggesting it as a general feature of the organization of biological membranes. These results demonstrate that polyunsaturated fats affect the composition and organization of biological membranes, suggesting a potential mechanism for the extensive effects of dietary fat on health and disease.
Rodenfels J.,Max Planck Institute of Molecular Cell Biology and Genetics |
Lavrynenko O.,Max Planck Institute of Molecular Cell Biology and Genetics |
Ayciriex S.,Max Planck Institute of Molecular Cell Biology and Genetics |
Sampaio J.L.,Max Planck Institute of Molecular Cell Biology and Genetics |
And 5 more authors.
Genes and Development | Year: 2014
In Drosophila larvae, growth and developmental timing are regulated by nutrition in a tightly coordinated fashion. The networks that couple these processes are far from understood. Here, we show that the intestine responds to nutrient availability by regulating production of a circulating lipoprotein-associated form of the signaling protein Hedgehog (Hh). Levels of circulating Hh tune the rates of growth and developmental timing in a coordinated fashion. Circulating Hh signals to the fat body to control larval growth. It regulates developmental timing by controlling ecdysteroid production in the prothoracic gland. Circulating Hh is especially important during starvation, when it is also required for mobilization of fat body triacylglycerol (TAG) stores. Thus, we demonstrate that Hh, previously known only for its local morphogenetic functions, also acts as a lipoprotein-associated endocrine hormone, coordinating the response of multiple tissues to nutrient availability. © 2014, Rodenfels et al.
Papan C.,Max Planck Institute of Molecular Cell Biology and Genetics |
Penkov S.,Max Planck Institute of Molecular Cell Biology and Genetics |
Herzog R.,Max Planck Institute of Molecular Cell Biology and Genetics |
Herzog R.,Lipotype GmbH |
And 3 more authors.
Analytical Chemistry | Year: 2014
A commonly accepted LIPID MAPS classification recognizes eight major lipid categories and over 550 classes, while new lipid classes are still being discovered by targeted biochemical approaches. Despite their compositional diversity, complex lipids such as glycerolipids, glycerophospholipids, saccharolipids, etc. are constructed from unique structural moieties, e.g., glycerol, fatty acids, choline, phosphate, and trehalose, that are linked by amide, ether, ester, or glycosidic bonds. This modular organization is also reflected in their MS/MS fragmentation pathways, such that common building blocks in different lipid classes tend to generate common fragments. We take advantage of this stereotyped fragmentation to systematically screen for new lipids sharing distant structural similarity to known lipid classes and have developed a discovery approach based on the computational querying of shotgun mass spectra by LipidXplorer software. We applied this concept for screening lipid extracts of C. elegans larvae at the dauer and L3 stages that represent alternative developmental programs executed in response to environmental challenges. The search, covering more than 1.5 million putative chemical compositions, identified a novel class of lyso-maradolipids specifically enriched in dauer larvae. © 2014 American Chemical Society.
Herzog R.,MPI of Molecular Cell Biology and Genetics |
Herzog R.,Lipotype GmbH |
Schwudke D.,Research Center Borstel |
Shevchenko A.,MPI of Molecular Cell Biology and Genetics
Current Protocols in Bioinformatics | Year: 2013
LipidXplorer is an open-source software kit that supports the identification and quantification of molecular species of any lipid class detected by shotgun experiments performed on any mass spectrometry platform. LipidXplorer does not rely on a database of reference spectra: instead, lipid identification routines are user defined in the declarative molecular fragmentation query language (MFQL). The software supports batch processing of multiple shotgun acquisitions by high-resolution mass mapping, precursor and neutral-loss scanning, and data-dependentMS/MSlending itself to a variety of lipidomics applications in cell biology and molecular medicine. © 2013 by John Wiley & Sons, Inc.
Klose C.,Lipotype GmbH |
Coskun U.,TU Dresden
BioSpektrum | Year: 2016
Shotgun lipidomics is the comprehensive and quantitative analysis of the lipid composition of biological and clinical samples. Here we describe the application and performance of the Lipotype shotgun lipidomics technology in clinical high throughput screening projects for the identification of disease-specific lipid patterns as well as in organ-wide analysis aiming at the systemic understanding of lipid-related physiological processes. © 2016, Springer-Verlag Berlin Heidelberg.
Surma M.A.,Wrocław University |
Surma M.A.,Lipotype GmbH |
Szczepaniak A.,Wrocław University |
Kroliczewski J.,Wrocław University
PLoS ONE | Year: 2014
The present paper is a systematic, comparative study on the reconstitution of an apocytochrome b6 purified from a heterologous system using a detergent-free method and reconstitution into liposomes performed using three different detergents: SDS, Triton X-100 and DM, and two methods of detergent removal by dialysis and using Bio-Beads. The product size, its distribution and zeta potential, and other parameters were monitored throughout the process. We found that zeta potential of proteoliposomes is correlated with reconstitution efficiency and, as such, can serve as a quick and convenient quality control for reconstitution experiments. We also advocate using detergent-free protein purification methods as they allow for an unfettered choice of detergent for reconstitution, which is the most crucial factor influencing the final product parameters. © 2014 Surma et al.
PubMed | Lipotype GmbH, Lund University, University of Stockholm, Gothenburg University and Aix - Marseille University
Type: Journal Article | Journal: Journal of the American Heart Association | Year: 2016
Diabetes mellitus (DM) and cardiovascular disease are associated with dyslipidemia, but the detailed lipid molecular pattern in both diseases remains unknown.We used shotgun mass spectrometry to determine serum levels of 255 molecular lipids in 316 controls, 171 DM, and 99 myocardial infarction (MI) events from a cohort derived from the Malm Diet and Cancer study. Orthogonal projections to latent structures analyses were conducted between the lipids and clinical parameters describing DM or MI. Fatty acid desaturases (FADS) and elongation of very long chain fatty acid protein 5 (ELOVL5) activities were estimated by calculating product to precursor ratios of polyunsaturated fatty acids in complex lipids. FADS genotypes encoding these desaturases were then tested for association with lipid levels and ratios. Differences in the levels of lipids belonging to the phosphatidylcholine and triacylglyceride (TAG) classes contributed the most to separating DM from controls. TAGs also played a dominating role in discriminating MI from controls. Levels of C18:2 fatty acids in complex lipids were lower both in DM and MI versus controls (DM, P=0.004; MI, P=6.0E-06) at least due to an acceleration in the metabolic flux from C18:2 to C20:4 (eg, increased estimated ELOVL5: DM, P=0.02; MI, P=0.04, and combined elongase-desaturase activities: DM, P=3.0E-06; MI, P=2.0E-06). Minor allele carriers of FADS genotypes were associated with increased levels of C18:2 (P0.007) and lower desaturase activity (P0.002).We demonstrate a possible relationship between decreased levels of C18:2 in complex lipids and DM or MI. We thereby highlight the importance of molecular lipids in the pathogenesis of both diseases.
PubMed | Lipotype GmbH and University of Montréal
Type: | Journal: Methods in molecular biology (Clifton, N.J.) | Year: 2015
Lipidomics is a rapidly growing technology for identification and quantification of a variety of cellular lipid molecules. Following the successful development and application of functional genomic technologies in yeast Saccharomyces cerevisiae, we witness a recent expansion of lipidomics applications in this model organism. The applications include detailed characterization of the yeast lipidome as well as screening for perturbed lipid phenotypes across hundreds of yeast gene deletion mutants. In this chapter, we describe sample handling, mass spectrometry, and bioinformatics methods developed for yeast lipidomics studies.