PCSK9 inhibition alters the lipidome of plasma and lipoprotein fractions.

Background And Aims: While inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) is known to result in dramatic lowering of LDL-cholesterol (LDL-C), it is poorly understood how it affects other lipid species and their metabolism. The aim of this study was to characterize the alterations in the lipidome of plasma and lipoprotein particles after administration of PCSK9 inhibiting antibody to patients with established coronary heart disease.

Methods: Plasma samples were obtained from patients undergoing a randomized placebo-controlled phase II trial (EQUATOR) for the safe and effective use of RG7652, a fully human monoclonal antibody inhibiting PCSK9 function.

Molecular lipid species in urinary exosomes as potential prostate cancer biomarkers.

Background: Exosomes have recently appeared as a novel source of noninvasive cancer biomarkers, since these nanovesicles contain molecules from cancer cells and can be detected in biofluids. We have here investigated the potential use of lipids in urinary exosomes as prostate cancer biomarkers.

Methods: A high-throughput mass spectrometry quantitative lipidomic analysis was performed to reveal the lipid composition of urinary exosomes in prostate cancer patients and healthy controls.

Cellular effects of fluorodeoxyglucose: Global changes in the lipidome and alteration in intracellular transport.

2-fluoro-2-deoxy-D-glucose (FDG), labeled with 18F radioisotope, is the most common imaging agent used for positron emission tomography (PET) in oncology. However, little is known about the cellular effects of FDG. Another glucose analogue, 2-deoxy-D-glucose (2DG), has been shown to affect many cellular functions, including intracellular transport and lipid metabolism, and has been found to improve the efficacy of cancer chemotherapeutic agents in vivo.

Novel actions of 2-deoxy-D-glucose: protection against Shiga toxins and changes in cellular lipids.

2-Deoxy-D-glucose (2DG) is a structural analogue of glucose with well-established applications as an inhibitor of glycolysis and N-glycosylation. Importantly, 2DG has been shown to improve the efficacy of several cancer chemotherapeutic agents in vivo and thus it is in clinical studies in combination with chemotherapy and radiotherapy. However, although 2DG has been demonstrated to modulate many cellular functions, including autophagy, apoptosis and cell cycle control, little is known about the effects of 2DG on intracellular transport, which is of great importance when predicting the effects of 2DG on therapeutic agents.

Quantitative lysophospholipidomics in human plasma and skin by LC-MS/MS.

Lysophospholipids (LPLs) are an essential family of lipids, which serve as bioactive molecules and as precursors and intermediates of the glycerophospholipid and sphingolipid metabolisms. In this work we primarily focused on the subgroup lysoglycerophospholipids that comprise a polar headgroup at the sn-3 position and a fatty acyl group at either the sn-1 or sn-2 position of the glycerol backbone giving rise to the two potential regioisomers 1-acyl-2-LPL and 2-acyl-1-LPL, respectively. We established a quantitative lysophospholipidomics method combining hydrophilic interaction chromatography (HILIC) with the scheduled multiple reaction monitoring (sMRM) algorithm for profiling a vast number of LPLs simultaneously, including the 1-acyl-2-LPL and 2-acyl-1-LPL regioisomers.

The ether lipid precursor hexadecylglycerol stimulates the release and changes the composition of exosomes derived from PC-3 cells.

Exosomes are vesicles released by cells after fusion of multivesicular bodies with the plasma membrane. In this study, we have investigated whether ether lipids affect the release of exosomes in PC-3 cells. To increase the cellular levels of ether lipids, the ether lipid precursor hexadecylglycerol was added to cells.

The ether lipid precursor hexadecylglycerol protects against Shiga toxins.

Shiga toxin-producing Escherichia coli bacteria cause hemorrhagic colitis and hemolytic uremic syndrome in humans. Currently, only supportive treatment is available for diagnosed patients. We show here that 24-h pretreatment with an ether lipid precursor, the alkylglycerol sn-1-O-hexadecylglycerol (HG), protects HEp-2 cells against Shiga toxin and Shiga toxin 2.

The ether lipid precursor hexadecylglycerol causes major changes in the lipidome of HEp-2 cells.

The ether-lipid precursor sn-1-O-hexadecylglycerol (HG) can be used to compensate for early metabolic defects in ether-lipid biosynthesis. To investigate a possible metabolic link between ether-linked phospholipids and the rest of the cellular lipidome, we incubated HEp-2 cells with HG. Mass spectrometry analysis revealed major changes in the lipidome of HG-treated cells compared to that of untreated cells or cells treated with palmitin, a control substance for HG containing an acyl group instead of the ether group.

Cell density-induced changes in lipid composition and intracellular trafficking.

Cell density is one of the extrinsic factors to which cells adapt their physiology when grown in culture. However, little is known about the molecular changes which occur during cell growth and how cellular responses are then modulated. In many cases, inhibitors, drugs or growth factors used for in vitro studies change the rate of cell proliferation, resulting in different cell densities in control and treated samples.

Metabolomic changes in fatty liver can be modified by dietary protein and calcium during energy restriction.

Aim: To characterise the effect of energy restriction (ER) on liver lipid and primary metabolite profile by using metabolomic approach. We also investigated whether the effect of energy restriction can be further enhanced by modification of dietary protein source and calcium.

Methods: Liver metabolomic profile of lean and obese C57Bl/6J mice (n = 10/group) were compared with two groups of weight-reduced mice.

Determination of monosaccharide composition in plant fiber materials by capillary zone electrophoresis.

The neutral sugar composition of acid hydrolyzed extracts of cellulose fiber samples, i.e. oat spelt, wheat straw, thermomechanica pulp (TMP) made of spruce, aspen stemwood, and bleached birch kraft pulp, was determined by a new capillary zone electrophoresis (CZE) method employing an alkaline background electrolyte.

Central carbon metabolism of Saccharomyces cerevisiae in anaerobic, oxygen-limited and fully aerobic steady-state conditions and following a shift to anaerobic conditions.

Saccharomyces cerevisiae CEN.PK113-1A was grown in glucose-limited chemostat culture with 0%, 0.5%, 1.

Heterologous expression and site-directed mutagenesis studies of two Trichoderma harzianum chitinases, Chit33 and Chit42, in Escherichia coli.

Heterologous expression of two fungal chitinases, Chit33 and Chit42, from Trichoderma harzianum was tested in the different compartments and on the surface of Escherichia coli cells. Our goal was to find a fast and efficient expression system for protein engineering and directed evolution studies of the two fungal enzymes. Cytoplasmic overexpression resulted in both cases in inclusion body formation, where active enzyme could be recovered after refolding.

Endosperm structure affects the malting quality of barley (Hordeum vulgare L.).

Twenty-seven barley (Hordeum vulgare L.) samples collected from growing sites in Scandinavia in 2001 and 2002 were examined to study the effect of endosperm structure on malting behavior. Samples were micromalted, and several malt characteristics were measured.

Development of a high-throughput format for solid-phase extraction of enantiomers using an immunosorbent in 384-well plates.

An antibody-based solid-phase extraction method for filtered 384-well plates was developed for a medical drug candidate having two enantiomeric forms in order to demonstrate the potential of the use of recombinant antibody fragments as specific and efficient immunosorbents. An immobilization method using a six-histidine tag of the antibody fragment and mild oxidation was applied in order to immobilize antibody fragments in an oriented and kinetically stable way that ensured high capacity of the antibody support. Phosphate buffer or plasma spiked with enantiomers were used as samples.