Conserved roles of C. elegans and human MANFs in sulfatide binding and cytoprotection.

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER) protein that can be secreted and protects dopamine neurons and cardiomyocytes from ER stress and apoptosis. The mechanism of action of extracellular MANF has long been elusive. From a genetic screen for mutants with abnormal ER stress response, we identified the gene Y54G2A.23 as the evolutionarily conserved C. elegans MANF orthologue. We find that MANF binds to the lipid sulfatide, also known as 3-O-sulfogalactosylceramide present in serum and outer-cell membrane leaflets, directly in isolated forms and in reconstituted lipid micelles. Sulfatide binding promotes cellular MANF uptake and cytoprotection from hypoxia-induced cell death. Heightened ER stress responses of MANF-null C. elegans mutants and mammalian cells are alleviated by human MANF in a sulfatide-dependent manner. Our results demonstrate conserved roles of MANF in sulfatide binding and ER stress response, supporting sulfatide as a long-sought lipid mediator of MANF's cytoprotection

Chronic visceral acid sphingomyelinase deficiency (Niemann-Pick disease type B) in 16 Polish patients: long-term follow-up

Abstract Background Acid sphingomyelinase deficiency (ASMD), due to mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene, is divided into infantile neurovisceral ASMD (Niemann-Pick type A), chronic neurovisceral ASMD (intermediate form, Niemann-Pick type A/B) and chronic visceral ASMD (Niemann-Pick type B). We conducted a long-term observational, single-center study including 16 patients with chronic visceral ASMD. Results 12 patients were diagnosed in childhood and 4 others in adulthood, the oldest at the age of 50. The mean time of follow-up was approximately 10 years (range: 6 months – 36 years). Splenomegaly was noted in all patients at diagnosis. Hepatomegaly was observed in 88% of patients. Moderately elevated (several-fold above the upper limit of normal values) serum transaminases were noted in 38% of patients. Cherry-red spots were found in five Gypsy children from one family and also in one adult Polish patient, a heterozygote for p.delR610 mutation. Dyslipidemia was noted in 50% of patients. Interstitial lung disease was diagnosed in 44% of patients. Plasmatic lysosphingomyelin (SPC) was elevated in all the patients except one with p.V36A homozygosity and a very mild phenotype also presenting with elevated plasmatic SPC-509 but normal chitotriosidase activity. The most common variant of SMPD1 gene was p.G166R. We found a previously unreported variant in exon 2 (c.491G > T, p.G164 V) in one patient. Conclusions Chronic visceral ASMD could constitute a slowly progressing disease with a relatively good outcome. The combined measurement of lysosphingomyelin (SPC) and lysospingomyelin-509 (SPC-509) is an essential method for the assessment of ASMD course

Lipidomická charakterizace exosomů izolovaných z lidské plazmy pomocí různých technik hmotnostní spektrometrie

Ultrahigh-performance supercritical fluid chromatography - mass spectrometry (UHPSFC/MS), ultrahigh-performance liquid chromatography - mass spectrometry (UHPLC/MS), and matrix-assisted laser desorption/ionization (MALDI) - MS techniques were used for the lipidomic characterization of exosomes isolated from human plasma. The high-throughput methods UHPSFC/MS and UHPLC/MS using a silica-based column containing sub-2 mu m particles enabled the lipid class separation and the quantitation based on exogenous class internal standards in < 7 minute run time. MALDI provided the complementary information on anionic lipid classes, such as sulfatides. The nontargeted analysis of 12 healthy volunteers was performed, and absolute molar concentration of 244 lipids in exosomes and 191 lipids in plasma belonging to 10 lipid classes were quantified. The statistical evaluation of data included principal component analysis, orthogonal partial least square discriminant analysis, S-plots, p-values, T-values, fold changes, false discovery rate, box plots, and correlation plots, which resulted in the information on lipid changes in exosomes in comparison to plasma. The major changes were detected in the composition of triacylglycerols, diacylglycerols, phosphatidylcholines, and lysophosphatidylcholines, whereby sphingomyelins, phosphatidylinositols, and sulfatides showed rather similar profiles in both biological matrices.Ultravysokoúčinná superkritická kapalinová chromatografie - hmotnostní spektrometrie (UHPSFC / MS), ultravysokoúčinná kapalinová chromatografie - hmotnostní spektrometrie (UHPLC / MS) a laserová desorpce / ionizace (MALDI) - MS byly použity pro lipidomickou charakterizaci exosomů izolovaných z lidské plazmy. Vysokoúčinné metody UHPSFC / MS a UHPLC / MS využívající kolonu na bázi oxidu křemičitého obsahující částice sub-2 um umožnily separaci lipidové třídy a kvantifikaci na základě interních standardů exogenní třídy v době běhu <7 minut. MALDI poskytl doplňující informace o třídách aniontových lipidů, jako jsou sulfatidy. Byla provedena necílená analýza 12 zdravých dobrovolníků a byla kvantifikována absolutní molární koncentrace 244 lipidů v exosomech a 191 lipidů v plazmě patřících do 10 lipidových tříd. Statistické vyhodnocení dat zahrnovalo analýzu hlavních složek, ortogonální částečnou diskriminační analýzu nejmenších čtverců, S-grafy, p-hodnoty, T-hodnoty, násobné změny, míru falešných objevů, krabicové grafy a korelační grafy, které vyústily v informace o lipidech změny v exosomech ve srovnání s plazmou. Hlavní změny byly detekovány ve složení triacylglycerolů, diacylglycerolů, fosfatidylcholinů a lysofosfatidylcholinů, přičemž sfingomyeliny, fosfatidylinositoly a sulfatidy vykazovaly v obou biologických matricích poměrně podobné profil

Conserved roles of C. elegans and human MANFs in sulfatide binding and cytoprotection.

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER) protein that can be secreted and protects dopamine neurons and cardiomyocytes from ER stress and apoptosis. The mechanism of action of extracellular MANF has long been elusive. From a genetic screen for mutants with abnormal ER stress response, we identified the gene Y54G2A.23 as the evolutionarily conserved C. elegans MANF orthologue. We find that MANF binds to the lipid sulfatide, also known as 3-O-sulfogalactosylceramide present in serum and outer-cell membrane leaflets, directly in isolated forms and in reconstituted lipid micelles. Sulfatide binding promotes cellular MANF uptake and cytoprotection from hypoxia-induced cell death. Heightened ER stress responses of MANF-null C. elegans mutants and mammalian cells are alleviated by human MANF in a sulfatide-dependent manner. Our results demonstrate conserved roles of MANF in sulfatide binding and ER stress response, supporting sulfatide as a long-sought lipid mediator of MANF's cytoprotection

Lipidomické profilování lidského séra umožňující detekci karcinomu slinivky břišní

Pancreatic cancer has the worst prognosis among all cancers. Cancer screening of body fluids may improve the survival time prognosis of patients, who are often diagnosed too late at an incurable stage. Several studies report the dysregulation of lipid metabolism in tumor cells, suggesting that changes in the blood lipidome may accompany tumor growth. Here we show that the comprehensive mass spectrometric determination of a wide range of serum lipids reveals statistically significant differences between pancreatic cancer patients and healthy controls, as visualized by multivariate data analysis. Three phases of biomarker discovery research (discovery, qualification, and verification) are applied for 830 samples in total, which shows the dysregulation of some very long chain sphingomyelins, ceramides, and (lyso) phosphatidylcholines. The sensitivity and specificity to diagnose pancreatic cancer are over 90%, which outperforms CA 19-9, especially at an early stage, and is comparable to established diagnostic imaging methods. Furthermore, selected lipid species indicate a potential as prognostic biomarkers.Rakovina slinivky má nejhorší prognózu ze všech nádorů. Screening nádorových onemocnění tělními tekutinami může zlepšit časovou prognózu přežití pacientů, kteří jsou často diagnostikováni příliš pozdě v nevyléčitelném stadiu. Několik studií uvádí dysregulaci metabolismu lipidů v nádorových buňkách, což naznačuje, že změny v krevním lipidomu mohou doprovázet růst nádoru. Zde ukazujeme, že komplexní hmotnostní spektrometrické stanovení širokého spektra sérových lipidů odhaluje statisticky významné rozdíly mezi pacienty s rakovinou pankreatu a zdravými kontrolami, jak je vizualizováno multivariační analýzou dat. Tři fáze výzkumu v oblasti objevování biomarkerů (objev, kvalifikace a verifikace) jsou aplikovány celkem na 830 vzorků, což prokazuje dysregulaci některých velmi dlouhých řetězců sfingomyelinů, ceramidů a (lyso)fosfatidylcholinů. Senzitivita a specificita k diagnostice karcinomu slinivky břišní je více než 90%, což překonává CA 19-9, zejména v raném stadiu, a je srovnatelná se zavedenými diagnostickými zobrazovacími metodami. Vybrané druhy lipidů navíc indikují potenciál jako prognostické biomarkery