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Easily accessible biomarkers are needed to diagnose cardiovascular disease precisely-particularly, to distinguish between disease subtypes that are encountered in clinical practice. Per the hypothesis that plasma miRNA is valuable for this purpose, we performed complete transcriptional profiling of an miRNA discovery-set in 14 samples: three patients with ST-elevated acute myocardial infarction (STEMI) at baseline and after three months of follow-up, four with stable ischaemic heart disease (stable-IHD) and four healthy age-matched volunteers. Our aim was to determine whether we could distinguish patients with unstable plaques from stable patients following a STEMI event. After analysing miRNA profiles, we conducted a validation study comparing three-month STEMI (n=40) with stable-IHD (n=35), which confirmed that miR-486-3P differentiates patients with three-month STEMI from those with stable-IHD (P=0.019).

Truls Gråberg,1 Lovisa Strömmer,1 Erik Hedman,2 Mehmet Uzunel,3 Ewa Ehrenborg,4 Ann-Charlotte Wikström5 1Division of Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, 2Department of Clinical Pharmacology, Karolinska University Hospital, 3Division of Therapeutic Immunology, Department of Laboratory Medicine, 4Atherosclerosis Research Unit, Department of Medicine, Solna, 5Unit of Translational Immunology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden Introduction: An assay to determine glucocorticoid (GC) responsiveness in humans could be used to monitor GC non-responsiveness in states of GC insufficiency and could provide a tool to adapt GC treatment to individual patients. We propose an ex vivo assay to test GC responsiveness in peripheral leukocytes. The assay was evaluated in a human experimental model of surgery-induced inflammation. Patients and methods: Changes in expression of the GC-regulated genes GILZ, IL1R2, FKBP5, and HLA-DR and glucocorticoid receptor alpha (GRα) were determined by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in peripheral leukocytes from surgical patients and healthy blood donors (total n=60) in response to low (1 nM) and high (1 µM) dexamethasone (DEX). The final selection of a suitable endogenous control gene was based on the studies of stability during DEX treatment and inflammation. Correlations between pre- and postoperative GC-induced gene expression, the postoperative systemic inflammatory and metabolic response (CRP, IL-6, white blood cell count, cytokines, resistin, free fatty acids, glucose, insulin, and adiponectin), and the clinical outcome were analyzed. The length of stay in the intensive care unit (ICU-LOS), the length of stay in the hospital, and postoperative complications were used to measure clinical outcome. Results: When the blood donors were compared to the patient

Context: Nonfasting (postprandial) triglyceride concentrations have emerged as a clinically significant cardiovascular disease risk factor that results from accumulation of remnant triglyceride-rich lipoproteins (TRLs) in the circulation. The remnant TRLs are cleared from the circulation by hepatic uptake, but the specific mechanisms involved are unclear. The syndecan-1 heparan sulfate proteoglycan (HSPG) pathway is important for the hepatic clearance of remnant TRLs in mice, but its relevance in humans is unclear. Objective: We sought to determine whether polymorphisms of the genes responsible for HSPG assembly and disassembly contribute to atherogenic dyslipoproteinemias in humans. Patients And Design: We performed an oral fat load in 68 healthy subjects. Lipoproteins (chylomicrons and very low density lipoproteins 1 and 2) were isolated from blood, and the area under curve and incremental area under curve for postprandial variables were calculated. Single nucleotide polymorphisms in genes encoding syndecan-1 and enzymes involved in the synthesis or degradation of HSPG were genotyped in the study subjects. Results: Our results indicate that the genetic variation rs2281279 in SULF2 associates with postprandial clearance of remnant TRLs and triglyceride levels in healthy subjects. Furthermore, the SNP rs2281279 in SULF2 associates with hepatic SULF2 mRNA levels. Conclusions: In humans, mild but clinically relevant postprandial hyperlipidemia

Lipoprotein lipase (LPL) hydrolyzes triglycerides in plasma lipoproteins causing release of fatty acids for metabolic purposes in muscles and adipose tissue. LPL in macrophages in the artery wall may, however, promote foam cell formation and atherosclerosis. Angiopoietin-like protein (ANGPTL) 4 inactivates LPL and ANGPTL4 expression is controlled by peroxisome proliferator-activated receptors (PPAR). The mechanisms for inactivation of LPL by ANGPTL4 was studied in THP-1 macrophages where active LPL is associated with cell surfaces in a heparin-releasable form, while LPL in the culture medium is mostly inactive. The PPAR delta agonist GW501516 had no effect on LPL mRNA, but increased ANGPTL4 mRNA and caused a marked reduction of the heparin-releasable LPL activity concomitantly with accumulation of inactive, monomeric LPL in the medium. Intracellular ANGPTL4 was monomeric, while dimers and tetramers of ANGPTL4 were present in the heparin-releasable fraction and medium. GW501516 caused an increase in the amount of ANGPTL4 oligomers on the cell surface that paralleled the decrease in LPL activity. Actinomycin D blocked the effects of GW501516 on ANGPTL4 oligomer formation and prevented the inactivation of LPL Antibodies against ANGPTL4 interfered with the inactivation of LPL. We conclude that inactivation of LPL in THP-1 macrophages primarily occurs on the cell surface where oligomers of ANGPTL4 are formed. (c) 2012 Elsevier Inc. All rights reserved.

Serum alanine aminotransferase (ALT) is used asa clinical marker to detect hepatic damage and hepatoxicity.Two isoforms of ALT have been identified, ALT1 and ALT2,which have identical enzymatic capacities and are detectedsimultaneously in human serum/plasma using classical clinicalchemical assays. Differences exist in the expression patterns ofthe ALT1 and ALT2 proteins in different organs which suggestthat changes in the proportion of ALT1 and ALT2 in plasmamay arise and reflect damage to different human organs.However, this has not been previously studied due to the lackof a selective methodology that can quantify both ALT1 andALT2 isoforms in the total ALT activity normally measuredin clinical samples. To the best of our knowledge, our currentstudy reveals for the first time, that under 3 different conditionsof liver damage (non-alcoholic fatty liver disease, hepatitis Cand during liver surgery) the leakage of ALT1 activity intoplasma greatly exceeds that of ALT2, and that the measurementof ALT1 during liver damage is equal to the measurement oftotal ALT activity. By contrast, during skeletal muscle injury,induced in volunteers by physical exertion, the leakage ofALT2 exceeds that of ALT1 and the proportion of circulatingALT isoforms changes accordingly. The ALT isoform changesoccurring in plasma reflect previously demonstrated relativecontents of ALT1 and ALT2 activities in human liver and skeletalmuscle. These data suggest that assessing the percentagecontribution of ALT1 and ALT2 activities to total ALT activityin plasma may distinguish hepatic from extrahepatic injuryusing the same standard analytical platform.

Objectives: Deficiency in the catabolism of triglyceride-rich lipoproteins is the main cause of childhood-onset chylomicronaemia syndrome. Missense mutations in lipoprotein lipase (LPL) or in proteins influencing LPL activity or stability have been shown to be critical determinants of chylomicronaemia syndrome. The main objective of the present study was to assess the primary deficiency in five cases of childhood-onset chylomicronaemia syndrome. Setting: Lipid clinic at a university hospital, Subjects: Subjects presenting with severe hypertriglyceridaemia and chylomicronaemia syndrome in which reduced LPL activity and mass was observed. Interventions: Analysis of LPL and GPIHBP1 genes. Results: Among the five patients, one novel homozygous missense mutation (p.C68Y) in exon 3 of GPIHBP1 was identified. The other four patients were homozygous for the common LPL mutation p.G188E. Conclusion: These findings provide further evidence that GPIHBP1 is involved in the catabolism of triglyceride-rich lipoproteins and plays a role in childhood-onset chylomicronaemia.