Day 2 :
Keynote Forum
Carl E Freter
Saint Louis University, USA
Keynote: Targeting cholesterol synthesis increases chemoimmuno-sensitivity in lymphoid malignancies
Time : 10:00-10:30
Biography:
Carl E Freter, MD, PhD, FACP is the Director of the Division of Hematology and Oncology at Saint Louis University. He is a tenured Professor of Medicine, Associate Director of the Saint Louis University Cancer Center and the Rosalie Fusz Endowed Chair of Hematology. He is also the Director of the Fellowship Program in Hematology and Oncology. He received his MD and PhD in Biochemistry at Washington University School of Medicine. He did his internship and residency training at Stanford University, and his fellowship in hematology/oncology at the National Cancer Institute at the NIH. Before coming to Saint Louis University in 2014, he was the Co-Director of the Ellis Fischel Cancer Center at the University of Missouri-Columbia, as well as the Director of the Division of Hematology and Oncology and the Fellowship Program in Hematology and Oncology.
Abstract:
Background: Cholesterol is an important factor with multiple effects on cancer development, drug resistance and chemoimmuno-sensitivity. Statins, cholesterol lowering drugs, can induce cancer cell apoptosis, but are also immunomodulatory and increase peripheral regulatory T cell numbers and function in vivo, and negatively interfere with CD-20 and rituximab-mediated activity. Our goal is to identify the alternative targets that could reduce cholesterol levels but do not interfere with T and B cells in the immunotherapy of blood cancers. Methods: MEC-2 cells, Raji cells and WAC3 cells as well as the peripheral blood mononuclear cells (PBMCs) from CLL patients were treated with cholesterol lowering agents, and analyzed the effect of these agents on cholesterol levels, CD-20 expression and distribution, and cell viability in the presence or absence of fludarabine, rituximab or their combinations. Results: We found that MEC-2 cells treated with cholesterol lowering agents (BIBB-515, YM-53601 or TAK-475) reduced total cellular cholesterol levels by 20%, and also significantly promoted CD-20 surface expression. Furthermore, treatment of cells with fludarabine, rituximab or their combinations in the presence of BIBB-515, YM-53601 or TAK-475 enhanced MEC-2 cell chemoimmunosensitivity measured by cell viability in MTT assays. The cholesterol lowering drugs also increase Raji and WAC3 cell chemoimmunosensitivity. More importantly, these cholesterol lowering agents also significantly enhanced chemoimmunosensitivity of the PBMCs from CLL patients. rnrnConclusion: Our data demonstrate that cholesterol lowering drugs (BIBB-515, YM53601 and TAK-475) enhance cell chemoimmunosensitivity without immunomodulatory T and B cell functions or their downstream signaling. These results provide a novel strategy which could be applied to the treatment of lymphoid malignancies.
Keynote Forum
G M Anantharamaiah
UAB School of Medicine, USA
Keynote: Apolipoprotein E mimetic: From theory to therapy
Time : 10:30-11:00
Biography:
G M Anantharamaiah is a Professor in the Department of Medicine. He joined the UAB faculty in 1982. His research involves use of apoA-I mimetic and apoE mimetic peptides, both these peptides to inhibit atherosclerosis in atherosclerosis sensitive mice, mechanisms of action of anti-atherogenic and anti-inflammatory peptides in relation to anti-inflammatory proteins present in HDL. In addition, apoE mimetic peptides enhance secretion of apoE and thus exert its additional beneficial effects not only in atherosclerosis but also in Alzhemier’s disease and in diabetes. He has published more than 200 papers on his research.
Abstract:
Apolipoprotein E (apoE) has a dual-domain structure, with a four helix bundle containing the receptor binding region in the amino terminal domain and a carboxyl terminal lipid binding domain. Peptides derived from the LDL receptor (LDL-R) binding region of apoE have been studied by a number of groups, with the primary focus being on the binding of the peptides to LDL-R. Based on the dual-domain structure, a peptide was designed with the highly cationic residues 141-150 from human apoE (hE) covalently bound to the lipid-associating Class A ï¡-helical peptide 18A and the amino and carboxyl termini blocked with acetyl and amide groups, respectively. This peptide, called Ac-hE18A-NH2 (in clinical development as AEM-28), was found to have striking cholesterol- and triglyceride-reducing and anti-inflammatory properties. Unlike statin drugs and proprotein convertase subtilisin/kexin type-9 (PCSK-9) inhibitors, these properties exist even in the absence of a functional LDL-R, with cholesterol reduction being mediated by binding to heparan sulfate proteoglycans (HSPG). Ac-hE18A-NH2 is currently undergoing Phase 1a/1b clinical trials, and has shown acceptable tolerability and promising efficacy. Thus, this and similar peptides have great potential for treatment of statin-resistant conditions such as familial hypercholesterolemia and acute hypertriglyceridemic pancreatitis.
- Lipid and Lipoprotein Metabolism, Lipids in molecular medicine
Location: Sausalito
Chair
Gerd Schmitz
University of Regensburg, Germany
Co-Chair
Ikuo Yokoyama
International University of Health and Welfare, Japan
Session Introduction
Gerd Schmitz
University of Regensburg, Germany
Title: Addition of high-density lipoprotein3 and Apo A-I antagonize the platelet storage lesion and the release of platelet extracellular vesicles
Time : 11:20-11:45
Biography:
Gerd Schmitz has completed his MD from the University of Cologne and Postdoctoral studies from the University of Münster, Germany. Until end of 2014, he was the director of the Institute of Laboatory Medicine and Transfusion Medicine at the University of Regensburg, Germany. Since then he started his own consulting company < www.lipoconsult.org >. He has published more than 350 papers in reputed journals and has been serving as an Editorial Board Member of several journals
Abstract:
During activation and senescence, platelets release increased amounts of platelet extracellular vesicles (PL-EVs). We established an in vitro model for size, proteomic, lipidomic and transcriptomic characterization of PL-EVs over 5 days in platelet concentrates to better understand the platelet storage lesion. After 5 days standard blood banking, PL-EVs were isolated by filtration and differential gradient ultracentrifugation into 5 platelet microvesicle subfractions (PL-MV F1-F5) and platelet exosomes (PL-EXs) and subjected to Nanoparticle Tracking Analysis, Flow Cytometry, proteomic/lipidomic mass spectrometry, miRNA-microarray profiling and deep sequencing. PL-EVs showed overlapping particle mean sizes of 180-260 nm, but differed significantly in composition. Less dense (F1-3), intermediate and dense (F5-EX) PL-EVs, are enriched in lipidomic and proteomic markers for plasma membrane, intracellular membranes/platelet granules and mitochondria. F1-F4 is enriched in free cholesterol, sphingomyelin(SM), dihydroSM and glycerophospholipids. F4-F5 are enriched with phosphatidylinositol, ceramides, lysophosphatidic acid, phosphatidylserine and cardiolpin species. Alpha-synuclein (81% of total expression) accumulated in F1-F2, amyloid beta precursor protein in F3-F4 (84%) and ApoE (88%) and ApoJ (92%) in F3-5. PL-EXs are enriched in lipid-raft and adhesion markers. During platelet senescence, HDL3/apoA-I significantly reduce PL-EVs by 62%, and the decrease correlates with the concentration of added apoA-I, and is mediated by SRB-I and CD36. Compared to platelets, PL-EVs enriched miRNAs related to neurodegenerative diseases. Different lipid and protein compositions of PL-EVs suggest their unique cellular origins, partly overlapping with platelet granule secretion. Dense PL-EVs might represent autophagic vesicles released during platelet activation/apoptosis and PL-EXs resemble lipid rafts, with a possible role in platelet coagulation and immunology. Segregation of alpha-synuclein and amyloid beta precursor protein, ApoE/J into less dense and dense PL-MVs, respectively, show their differential carrier role of neurological disease-related cargo. HDL3/apoA-I influences membrane homeostasis of platelets by reduction of PL-EV release during platelet senescence, improving intracellular lipid processing/vesicle transport and increasing cholesterol CE-efflux
Douglas S Conklin
State University of New York, USA
Title: Lipogenesis in HER2/neu positive breast cancer cells
Time : 11:45-12:10
Biography:
Douglas S Conklin is an Associate Professor at the Cancer Research Center at the State University of New York, University at Albany. He received his Doctoral degree at the University of Wisconsin-Madison and was a Post-doctoral fellow at Cold Spring Harbor Laboratory. His research focus is on functional genomics of cancer
Abstract:
Alterations in lipid metabolism have been reported in many types of cancer. Lipids have been implicated in a number of processes important to cancer cells. Recent work has shown that HER2/neu-positive breast cancer cells rely on a unique lipogenic Warburg-like metabolism for survival and aggressive behavior. These cells are dependent on fatty acid synthesis, show markedly increased levels of stored fats and disruption of the synthetic process results in apoptosis. The pathway is operating at its limits in HER2/neu-positive cells and addition of physiological doses of exogenous palmitate induces cell death. HER2-normal cells are not affected. Transcriptional profiling and computational analyses showed that palmitate induced functionally distinct transcriptional programs in HER2-normal MCF7 and HER2/neu-positive SKBR3 breast cancer cells. In HER2/neu-positive cells, palmitate activated an ER-stress response network and reduced HER2 and HER3 protein levels sensitizing the cells to treatment with trastuzumab. Global metabolite profiling data identified affected metabolic pathways and were integrated in a multi-omics network analysis. The growth of HER2-normal MCF7 cells was unaffected by exogenous palmitate although several species of neutral lipids increased as expected. The predominant upregulated lipid species in HER2/neu-positive SKBR3 cells was the novel bioactive lipid N-palmitoylglycine. In addition, the cells exhibited AMPK activation, inhibition of fatty acid synthesis and significantly altered glutamine, glucose and serine/glycine metabolism. Limiting the availability of glutamine significantly ameliorated the lipotoxic effects of palmitate reversing the transcriptional effects. Our results indicate that the lipogenic phenotype of HER2/neu-positive breast cancer cells places metabolic constraints on HER2-mediated oncogenic signaling and therapy
Frances T Yen
University of Lorraine, France
Title: The lipolysis stimulated lipoprotein receptor, LSR, as molecular link explaining the link between dyslipidemia, obesity and neurodegenerative diseases
Time : 12:10-12:35
Biography:
Frances T Yen completed her PhD in Nutritional Biochemistry at the University of Illinois at Urbana-Champaign, and her Postdoctoral studies at Columbia University College of Physicians and Surgeons in New York and Louisiana State University Medical Center in New Orleans. She is a Director of research at INSERM, and is currently team leader of BFLA (Bioavailability and functionnalities of dietary lipids) of the URAFPA laboratory at the University of Lorraine. She has published over 30 papers in reputable journals, is co-inventor of 10 patents, and has served as reviewer for journals including Diabetes and PloS One
Abstract:
Dyslipidemia is often associated with obesity, and together represent significant risk factors for age-related diseases including cardiovascular, metabolic and neurodegenerative disorders. Lipoproteins provide the means by which lipid status is maintained through a number of complex regulatory pathways that involve lipoprotein receptors, enzymes, transporters, and transfer proteins. We have demonstrated the role of the lipolysis stimulated lipoprotein receptor, LSR in the removal of triglyceride (TG)-rich lipoproteins from the circulation during the post-prandial phase. Partial reduction of expression of LSR in LSR+/- mice leads to increased postprandial TG levels, as well as decreased capacity for the removal of lipid particles from the plasma. Furthermore, these moderately hyperlipidemic mice demonstrate higher weight gain as compared to their control littermates either with age, or when placed on a high-fat diet. When aged mice were subjected to amyloid stress by intracerebroventricular injection of the oligomeric form of β-amyloid peptide (Aβ), behaviorial and biochemical analyses revealed increased deleterious effects in LSR+/- mice as compared to their control littermates. Furthermore, Aβ-induced changes in cortical cholesterol content were negatively correlated with the behaviorial changes measured. Immunohistochemical and GC MS analyses revealed potential changes in brain membrane cholesterol trafficking and metabolism which may be the underlying reason for the increased susceptibility of LSR+/- mice to Aβ peptdies. We therefore conclude that LSR and its dependent pathways may provide the missing link to explain the increased risk of neurodegenerative diseases associated with dyslipidemia and obesity, and may prove to be useful therapeutical targets for preventive and curative treatments
Nilay V Patel
California State University, Fullerton, USA
Title: Inhibition of cholesterol synthesis increases secretion of apolipoprotein E (apoE) from human astrocytoma and liver hepatocyte cells
Time : 12:35-13:00
Biography:
Nilay Patel received his Ph. D. in Neurobiology and Behavior from SUNY Stony Brook. He was a post-doctoral fellow in Dr. Caleb Finch’s group at USC, and a Beckman Research Fellow in Dr. Barry Forman’s group at City of Hope. He is an Associate Professor in Department of Biological Science at California State University, Fullerton, and Director of CIRM-funded Bridges to Stem Cell Research. His research focuses on identification of novel regulators of apoE gene expression
Abstract:
Apolipoprotein E (apoE) genotype is the biggest genetic risk factor Alzheimer’s disease (AD). ApoE is the primary lipid carrier in the brain, and is involved in brain cholesterol homeostasis and neuronal repair. It is thought that the e4 isoform increases risk for AD due to inadequate neuronal repair capabilities, and other deleterious effects such as lysosomal dysfunction and aggregation with Abeta peptide. Apomine and simvastatin are potent cholesterol-reducing compounds that mediates their actions through inhibition of HMGCoA-reductase and activation of SREBP2. We have found that under serum-free conditions, these two compounds increase apoE secretion and increase expression of LDLR and ApoER2 (apoE receptors) from human HepG2 liver hepatocyte cells. Addition of LDL to these treatments in serum-free medium suppressed induction of apoE by these compounds. Consistently, we found a strong negative correlation between cellular cholesterol levels and secreted apoE. Our results suggest that apomine and simvastatin regulate apoE expression at both the transcriptional and post-translational levels, and that these effects seem to be indirectly through alterations in cholesterol levels
Myung-Sook Choi
Kyungpook National University, Korea
Title: Green tea extract supplement enhances insulin sensitivity via regulation of plasma adipokine levels and transcriptional response in diet-induced obesity mice
Time : 14:00-14:25
Biography:
Myung-Sook Choi has completed his PhD in Texas Woman’s University, and Post-doctoral studies in North Texas State University and Cincinnati University. She is a Professor in Department of Food Science and Nutrition and the Director of Center of Food and Nutritional Genomics in Kyungpook National University. She has published more than 220 papers in international journals on nutrition and medicine and has been serving as an Editorial Board Member of several international journals
Abstract:
Obesity-induced inflammation play a pathogenic role in development of insulin resistance, and various adipokines are linked to inflammation. Green tea, one of oriental herbal teas, is well known to have beneficial effects on obesity. However, changes in transcriptional profiles in response to green tea are little known and still needs to be elucidated. In the present study, we investigated the effect of green tea extract (GT) on phenotype characteristics and elucidated anti-obesity mechanism based on RNA-sequencing analysis of transcriptomic profiles in an animal model of diet-induced obesity. C57BL/6J mice (4-week-old, Male) were fed a normal diet (16.58% kcal from fat, ND), high-fat diet (60% kcal from fat, HFD), and HFD supplemented with 0.25% (w/w) GT. They were given free access to food and distilled water for 12 weeks. GT supplement significantly decreased fat mass, body weight as well as plasma of triglycerides, cholesterol, and HDL-cholesterol levels compared to HFD group. Also, GT decreased plasma glucose, insulin resistance index (HOMA-IR) and improved glucose tolerance. GT led significant decrease in plasma leptine, IL-6, TNF-alpha, MCP-1, IFN-gamma levels and leptin:adiponectine ratio. Moreover, mRNA sequencing analysis revealed that GT improved insulin resistance by up-regulating glucose transporter type 4(GLUT4) gene expression in epididymal WAT. In addition, GT up-regulated genes involved in glucose metabolism and lipid metabolism, such as IRS, PECK, HSL, ACC, SCD1 and SREBP1c. Together, our findings suggest that green tea is one of bioactive material for improving HFD-induced insulin resistance by regulating glucose metabolism and plasma adipokines levels as well as expression of inflammation-related gene
Mohammad-Saeid Jami
Shahrekord University of Medical Sciences, Iran
Title: Proteomic analyses reveal distinct roles for L DOPA and Edaravone in protection of neurons against oxidative stress in
Time : 14:25-14:50
Biography:
Mohammad Saeid Jami has a PhD in molecular biology and biotechnology from the University of Leon (Spain). He has also been performing postdoc researches since 2011. He is assistant proffesor at Shahrekord University of Medical Sciences, School of Medicine. He has published more than 12 papers in the field of molecular biology and has been serving as an editorial board member of CCO and JMBR
Abstract:
Parkinson's disease (PD) is the second most common neurodegenerative movement disorder caused by preferential dopaminergic neuronal cell death in the substantia nigra, a process also influenced by oxidative stress. L-3,4-dihydroxyphenylalanine (L-DOPA) represents the main treatment route for motor symptoms associated with PD. Although L-DOPA has no direct antioxidant function, L-DOPA itself may induce low level of oxidative stress that in turn stimulates endogenous antioxidant mechanisms. Conversely, 3-methyl-1-phenyl-2-pyrazolin-5-one (Edaravone) is a neuroprotective suplement that act as potent antioxidants protecting against oxidative stress and neuronal apoptosis. In this study we performed a two-dimensional gel electrophoresis (2DE)-based proteomic study to gain further insight into the mechanism in which L-DOPA or Edaravone can influence the toxic effects of H2O2 in neuronal cells. We observed that oxidative stress affects the metabolic routes as well as cytoskeletal integrity and that neuronal cells respond to oxidative conditions by enhancing numerous survival pathways. We further show that L-DOPA and Edaravone have distinctive effects in response to oxidative stress. Exposure to L-DOPA can aid hypoxia condition in cells and therefore induction of ORP150 with its concomitant cytoprotective effects. Edaravone appears to protect neuronal cells against oxidative stress via induction of Peroxiredoxin-2 and inhibition of apoptosis. Our study sheds light on the molecular interplay linking together oxidative stress, L-DOPA and Edaravone in neuronal cells
Sandra Buratta
University of Perugia, Italy
Title: Oncogene-induced senescence modify lipid composition of exosomes released from H-RasV12 expressing cells
Time : 14:50-15:15
Biography:
Sandra Buratta is a permanent researcher at the Department of Chemistry, Biology and Biotecnhology, University of Perugia, Italy. In the last decade her research focused on several aspects of phospholipid metabolism, with the main aim to define the role of enzymes involved in the biosynthesis and replacement of membrane phospholipids in several cellular processes. Particular attention has dedicated to the role of phosphatidylserine and of the enzymes of its metabolism in signal transduction and apoptosis. Her present research focus on cellular effect associated to drug-induced phospholipidosis and on the role of lipids in exosomes fate and bioactivity
Abstract:
Cell proliferation induced by oncogene activation is restrained by cellular senescence, which acts as barriers in pre-neoplastic lesions. Senescent cells show proliferation arrest, flat morphology, activation of senescent associated β-galactosidase and acquisition of a specific secretory phenotype. Exosomes, 30-100 nm extracellular vesicles derived from the endosomal system, have been recently implicated in a variety of biological processes including the transfer senescence signals to surrounding cells. Similar to proteins and miRNA, lipid species enriched in exosomes are different to those of parental cells. A detailed analysis of exosomal lipid composition could be useful to understand the role of lipids in the functional response of target cells resulting in a senescent phenotype. In this study, lipid profile of human fibroblasts transfected with H-RasV12 and their released exosomes was analyzed by LC-MS/MS and GC-MS, and compared to mock transfected cells and their released exosomes. Results showed alteration in cell lipid composition during senescence. Relative quantification and comparison of exosomes versus the corresponding cell lipid profiles reveals an enrichment of lysophosphatidylcholine, ether-phosphatidylcholine (PCether) and sphyngomyelin (SM). Furthermore, remodeling and changes in the amount of specific lipid species of diacyl-PC, PCether and SM in exosomes released by senescent cells were detected. Overall results confirmed that lipid composition of exosomes is distinct from parental cells. Moreover, an increased release of exosomes with specific lipid composition was shown to be associated to H-Ras-induced senescence, suggesting a specific role of exosomal lipids in the spreading of senescence signals to surrounding cells