Publications by authors named "Christian M Madsen"

24 Publications

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Novel Insights From Human Studies on the Role of High-Density Lipoprotein in Mortality and Noncardiovascular Disease.

Arterioscler Thromb Vasc Biol 2021 01 24;41(1):128-140. Epub 2020 Nov 24.

Department of Clinical Biochemistry (C.M.M., A.V., B.G.N.), Herlev and Gentofte Hospital, Copenhagen University Hospital, Denmark.

The vast majority of research about HDL (high-density lipoprotein) has for decades revolved around the possible role of HDL in atherosclerosis and its therapeutic potential within cardiovascular disease prevention; however, failures with therapies aimed at increasing HDL cholesterol has left questions as to what the role and function of HDL in human health and disease is. Recent observational studies have further shown that extreme high HDL cholesterol is associated with high mortality leading to speculations that HDL could in some instances be harmful. In addition, evidence from observational, and to a lesser extent genetic studies has emerged indicating that HDL might be associated with the development of other major noncardiovascular diseases, such as infectious disease, autoimmune disease, cancer, type 2 diabetes, kidney disease, and lung disease. In this review, we discuss (1) the association between extreme high HDL cholesterol and mortality and (2) the emerging human evidence linking HDL to several major diseases outside the realm of cardiovascular disease.
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http://dx.doi.org/10.1161/ATVBAHA.120.314050DOI Listing
January 2021

Inhibition of Cholesteryl Ester Transfer Protein Preserves High-Density Lipoprotein Cholesterol and Improves Survival in Sepsis.

Circulation 2021 Mar 24;143(9):921-934. Epub 2020 Nov 24.

Centre for Heart Lung Innovation (M.T., T.P., L.B., H.J.K., J.A.R., K.R.W., J.H.B., L.R.B.), University of British Columbia, Vancouver, Canada.

Background: The high-density lipoprotein hypothesis of atherosclerosis has been challenged by clinical trials of cholesteryl ester transfer protein (CETP) inhibitors, which failed to show significant reductions in cardiovascular events. Plasma levels of high-density lipoprotein cholesterol (HDL-C) decline drastically during sepsis, and this phenomenon is explained, in part, by the activity of CETP, a major determinant of plasma HDL-C levels. We tested the hypothesis that genetic or pharmacological inhibition of CETP would preserve high-density lipoprotein levels and decrease mortality in clinical cohorts and animal models of sepsis.

Methods: We examined the effect of a gain-of-function variant in (rs1800777, p.Arg468Gln) and a genetic score for decreased function on 28-day sepsis survival using Cox proportional hazard models adjusted for age and sex in the UK Biobank (n=5949), iSPAAR (Identification of SNPs Predisposing to Altered Acute Lung Injury Risk; n=882), Copenhagen General Population Study (n=2068), Copenhagen City Heart Study (n=493), Early Infection (n=200), St Paul's Intensive Care Unit 2 (n=203), and Vasopressin Versus Norepinephrine Infusion in Patients With Septic Shock studies (n=632). We then studied the effect of the CETP inhibitor, anacetrapib, in adult female APOE*3-Leiden mice with or without human CETP expression using the cecal-ligation and puncture model of sepsis.

Results: A fixed-effect meta-analysis of all 7 cohorts found that the gain-of-function variant was significantly associated with increased risk of acute sepsis mortality (hazard ratio, 1.44 [95% CI, 1.22-1.70]; <0.0001). In addition, a genetic score for decreased CETP function was associated with significantly decreased sepsis mortality in the UK Biobank (hazard ratio, 0.77 [95% CI, 0.59-1.00] per 1 mmol/L increase in HDL-C) and iSPAAR cohorts (hazard ratio, 0.60 [95% CI, 0.37-0.98] per 1 mmol/L increase in HDL-C). APOE*3-Leiden.CETP mice treated with anacetrapib had preserved levels of HDL-C and apolipoprotein-AI and increased survival relative to placebo treatment (70.6% versus 35.3%, Log-rank =0.03), whereas there was no effect of anacetrapib on the survival of APOE*3-Leiden mice that did not express (50.0% versus 42.9%, Log-rank =0.87).

Conclusions: Clinical genetics and humanized mouse models suggest that inhibiting CETP may preserve high-density lipoprotein levels and improve outcomes for individuals with sepsis.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.120.048568DOI Listing
March 2021

Genetic Variants Associated With Increased Plasma Levels of Triglycerides, via Effects on the Lipoprotein Lipase Pathway, Increase Risk of Acute Pancreatitis.

Clin Gastroenterol Hepatol 2020 Aug 12. Epub 2020 Aug 12.

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark; The Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; The Copenhagen City Heart Study, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Frederiksberg, Denmark. Electronic address:

Background & Aims: Almost one third of adults in the West have increased plasma levels of triglycerides. Even mild to moderate hypertriglyceridemia (2-10 mmol/L or 177-886 mg/dL) is associated with an increased risk of acute pancreatitis. However, it is not clear whether hypertriglyceridemia is a cause or result of acute pancreatitis. Lipoprotein lipase degrades plasma triglycerides. Variants in LPL, APOA5, APOC3, ANGPTL3, and ANGPTL4, which regulate the lipoprotein lipase pathway, result in increased or reduced plasma triglyceride levels. We investigated associations between these variants and acute pancreatitis in a study of the general population.

Methods: In a prospective cohort study, men and women randomly selected from the area of Copenhagen were invited to complete a questionnaire, undergo a physical examination, and provide blood samples for biochemical and genetic analyses, from 2003 through 2015. We obtained triglyceride measurements from 117,427 participants. We examined for 15 genetic variants that are associated with lipoprotein lipase function in DNA samples from 102,888 participants and analyzed data from 117,427 participants in observational analyses. Diagnoses of acute pancreatitis (970 diagnoses among participants in the genetic analysis and 527 among participants in the observational study) were obtained from Danish registries. We performed a 1-sample Mendelian randomization analysis in which specific variants were used as markers of the plasma level of triglycerides to determine the association between the plasma level of triglyceride and acute pancreatitis. We calculated unweighted, internally weighted, and externally weighted allele scores for each participant by adding numbers of triglyceride-increasing alleles.

Results: The highest genetic allele score correlated with a higher plasma level of triglycerides of 0.54 mmol/L (48 mg/dL). Among participants with the highest vs the lowest genetic allele score, the odds ratio for acute pancreatitis was 1.55 (95% CI, 1.08-2.23). Using instrumental variable analysis, integrating the effect of genotype on both triglycerides levels and risk of acute pancreatitis, we associated higher unweighted allele scores with an increased risk of acute pancreatitis (odds ratio [OR], 1.76; 95% CI, 1.16-2.65), as well as internally weighted higher allele scores (OR, 1.41; 95% CI, 1.01-1.97) and externally weighted higher allele scores (OR, 1.44; 95% CI, 1.01-2.04). Every 1 mmol/L (89 mg/dL) increase in triglycerides was observationally associated with an increase in OR of 1.09 (95% CI, 1.05-1.14) after multivariable adjustment.

Conclusions: Based on an analysis of individuals with genetic variants associated with an increased level of triglycerides, via their effects on the lipoprotein lipase pathway, we associated an increased plasma levels of triglycerides with an increased risk of acute pancreatitis. Strategies to reduce plasma levels of triglycerides, by increasing lipoprotein lipase function, might be developed for prevention of acute pancreatitis.
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http://dx.doi.org/10.1016/j.cgh.2020.08.016DOI Listing
August 2020

Worldwide Prevalence of Familial Hypercholesterolemia: Meta-Analyses of 11 Million Subjects.

J Am Coll Cardiol 2020 05;75(20):2553-2566

Department of Clinical Biochemistry and the Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. Electronic address:

Background: Despite the greater prevalence of familial hypercholesterolemia (FH) in subjects with ischemic heart disease (IHD), premature IHD, and severe hypercholesterolemia (low-density lipoprotein ≥190 mg/dl), overall prevalence estimates are not available.

Objectives: The aim of this study was to provide worldwide estimates of FH prevalence in subjects with IHD, premature IHD, and severe hypercholesterolemia compared with those in the general population.

Methods: In this systematic review and meta-analyses, Embase, PubMed, and the Web of Science were searched until June 3, 2019, for peer-reviewed papers and conference abstracts reporting heterozygous FH prevalence in nonfounder populations, revealing 104 studies eligible for inclusion.

Results: Estimates of FH prevalence were pooled using random-effects meta-analyses and were 0.32% (95% confidence interval [CI]: 0.26% to 0.39% [corresponding to 1:313]) among 10,921,310 unique subjects in the general population (33,036 patients with FH) on the basis of 44 studies, 3.2% (95% CI: 2.2% to 4.3% [1:31]) among 84,479 unique subjects with IHD (2,103 patients with FH) on the basis of 28 studies, 6.7% (95% CI: 4.9% to 8.7% [1:15]) among 31,316 unique subjects with premature IHD (1,471 patients with FH) on the basis of 32 studies, and 7.2% (95% CI: 4.6% to 10.8% [1:14]) among 17,728 unique subjects with severe hypercholesterolemia (920 patients with FH) on the basis of 7 studies. FH prevalence in the general population was similar using genetic versus clinical diagnoses. Seventeen of 195 countries (9%) in the world have reported FH prevalence for the general population, leaving 178 (91%) countries in the world with unknown prevalence.

Conclusions: Compared with 1:313 among subjects in the general population, FH prevalence is 10-fold higher among those with IHD, 20-fold higher among those with premature IHD, and 23-fold higher among those with severe hypercholesterolemia. The prevalence of FH is unknown in 90% of countries in the world.
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http://dx.doi.org/10.1016/j.jacc.2020.03.057DOI Listing
May 2020

Thyroid-stimulating hormone (TSH) is associated with 30-day mortality in hip fracture patients.

Eur J Trauma Emerg Surg 2019 Nov 6. Epub 2019 Nov 6.

Department of Clinical Biochemistry, Hvidovre Hospital, Kettegaard Alle 30, 2650, Hvidovre, Denmark.

Purpose: The aim of this study is to assess the possible association between thyroid-stimulating hormone (TSH) and mortality in hip fracture patients.

Patients And Methods: The study is based on a hip fracture database from Bispebjerg University Hospital (Copenhagen, Denmark). This database includes all hip fracture patients (ICD-10 codes DS720 (femoral neck), DS721 (pertrochanteric), and DS722 (subtrochanteric)) admitted to Bispebjerg Hospital from 1996 to 2012. From this database, we identified all surgically treated hip fracture patients aged > 60 years with available plasma TSH-measurements at admission.

Results: Of the 914 included patients (24% men and 76% women), 10.5% died within 30 days. At inclusion, 161 (17.6%) of the patients were hyperthyroid (TSH < 0.65 mIU/L), 58 (6.4%) were hypothyroid (TSH > 4.8 mIU/L), while 695 (76.0%) were euthyroid (0.65 < TSH < 4.80 mIU/L), p = 0.03. Mortality was significantly higher in the two higher quartiles of TSH [Q3 (13.0%) and Q4 (15.4%)] compared to the two lower quartiles [Q1 (7.4%) and Q2 (6.2%), p = 0.0003. After adjustment for age, sex and Charlson Comorbidity Index (CCI) in a Cox proportional hazard model, the risk of 30-day mortality continued to be increased in patients with TSH above the median as compared to patients with TSH below the median (HR 2.1 (1.4-3.3), p = 0.0006].

Conclusion: The study demonstrates increased 30-day mortality in surgically treated hip fracture patients with plasma TSH levels above the median (1.41 mIU/L) at admission, even after adjusting for age, sex and CCI.
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http://dx.doi.org/10.1007/s00068-019-01260-9DOI Listing
November 2019

Body Mass Index, Triglycerides, and Risk of Acute Pancreatitis: A Population-Based Study of 118 000 Individuals.

J Clin Endocrinol Metab 2020 01;105(1)

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Borgmester Ib Juuls vej, Herlev, Denmark.

Objective: The incidence of acute pancreatitis is rising worldwide and currently no curative treatment exists. Clarification of preventable risk factors is important for the reduction of morbidity and mortality from acute pancreatitis. In this study, we tested the hypothesis that the risk of acute pancreatitis associated with body mass index (BMI) is partly mediated through elevated triglycerides.

Design: We included 118 085 individuals from 2 prospective cohort studies, the Copenhagen City Heart Study and the Copenhagen General Population Study, with BMI measured at baseline. Diagnosis of acute pancreatitis was assessed from the national Danish registries, as hospitalization or death due to acute pancreatitis.

Results: Higher BMI was associated with higher risk of acute pancreatitis with a multivariable-adjusted hazard ratio of 1.4 (95% CI, 1.1-1.8) for BMI of 25-29.9, 2.1 (1.6-2.9) for BMI of 30-34.9, and 2.8 (1.8-4.3) for BMI > 35, compared with individuals with BMI of 18.5-24.9. Triglycerides mediated 29% (95% CI, 12%-46%; P = 0.001) of the association between BMI and risk of acute pancreatitis in the age- and sex-adjusted model and 22% (6%-39%; P = 0.008) in the multivariable-adjusted model.

Conclusion: Higher BMI is associated with higher risk of acute pancreatitis in individuals from the general population, partly mediated through higher triglycerides. This indicates a potential for preventing acute pancreatitis by reducing BMI and triglycerides in individuals with high values.
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http://dx.doi.org/10.1210/clinem/dgz059DOI Listing
January 2020

Lipoprotein(a)-Lowering by 50 mg/dL (105 nmol/L) May Be Needed to Reduce Cardiovascular Disease 20% in Secondary Prevention: A Population-Based Study.

Arterioscler Thromb Vasc Biol 2020 01 3;40(1):255-266. Epub 2019 Oct 3.

From the Department of Clinical Biochemistry (C.M.M., P.R.K., A.L., A.V., B.G.N.), Copenhagen University Hospital, Denmark.

Objective: High Lp(a) (lipoprotein[a]) cause cardiovascular disease (CVD) in a primary prevention setting; however, it is debated whether high Lp(a) lead to recurrent CVD events. We tested the latter hypothesis and estimated the Lp(a)-lowering needed for 5 years to reduce CVD events in a secondary prevention setting. Approach and Results: From the CGPS (Copenhagen General Population Study; 2003-2015) of 58 527 individuals with measurements of Lp(a), 2527 aged 20 to 79 with a history of CVD were studied. The primary end point was major adverse cardiovascular event (MACE). We also studied 1115 individuals with CVD from the CCHS (Copenhagen City Heart Study; 1991-1994) and the CIHDS (Copenhagen Ischemic Heart Disease Study; 1991-1993). During a median follow-up of 5 years (range, 0-13), 493 individuals (20%) experienced a MACE in the CGPS. MACE incidence rates per 1000 person-years were 29 (95% CI, 25-34) for individuals with Lp(a)<10 mg/dL, 35 (30-41) for 10 to 49 mg/dL, 42 (34-51) for 50 to 99 mg/dL, and 54 (42-70) for ≥100 mg/dL. Compared with individuals with Lp(a)<10 mg/dL (18 nmol/L), the multifactorially adjusted MACE incidence rate ratios were 1.28 (95% CI, 1.03-1.58) for 10 to 49 mg/dL (18-104 nmol/L), 1.44 (1.12-1.85) for 50 to 99 mg/dL (105-213 nmol/L), and 2.14 (1.57-2.92) for ≥100 mg/dL (214 nmol/L). Independent confirmation was obtained in individuals from the CCHS and CIHDS. To achieve 20% and 40% MACE risk reduction in secondary prevention, we estimated that plasma Lp(a) should be lowered by 50 mg/dL (95% CI, 27-138; 105 nmol/L [55-297]) and 99 mg/dL (95% CI, 54-273; 212 nmol/L [114-592]) for 5 years.

Conclusions: High concentrations of Lp(a) are associated with high risk of recurrent CVD in individuals from the general population. This study suggests that Lp(a)-lowering by 50 mg/dL (105 nmol/L) short-term (ie, 5 years) may reduce CVD by 20% in a secondary prevention setting.
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http://dx.doi.org/10.1161/ATVBAHA.119.312951DOI Listing
January 2020

Excess mortality following hip fracture in patients with diabetes according to age: a nationwide population-based cohort study of 154,047 hip fracture patients.

Age Ageing 2019 07;48(4):559-563

Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.

Objective: to test the hypothesis that excess mortality conferred by diabetes following hip fracture decreases with advancing age.

Methods: a nationwide population-based cohort study including 154,047 patients who were admitted with a hip fracture in Denmark from 1996 to 2012. Information on hip fracture diagnosis, diabetes, other comorbidities, and the primary outcome all-cause mortality was collected using the national Danish health registries. The association between diabetes and all-cause mortality according to age was assessed using Cox proportional hazards regression in the age categories: <50, 50-59, 60-69, 70-79, 80-89 and ≥90 years.

Results: during a median follow-up of 3 years (interquartile range: 1-6 years, 603,091 person-years) 114,990 died from any cause. In total, 8% (n = 12,158) of the patients had diabetes at baseline and had unadjusted, and age, sex and Charlson Comorbidity Index adjusted hazard ratios for all-cause mortality of 1.19 (95% confidence interval: 1.16-1.21) and 1.14 (1.12-1.17) as compared to patients without diabetes. The sex and Charlson Comorbidity Index adjusted hazard ratios according to age were 1.64 (1.34-2.02) for patients <50 years, 1.26 (1.12-1.40) for patients 50-59 years, 1.21 (1.13-1.29) for patients 60-69 years, 1.11 (1.07-1.16) for patients 70-79 years, 1.10 (1.07-1.14) for patients 80-89 years and 1.09 (1.02-1.16) for patients ≥90 years. There was a statistically significant interaction between diabetes and age (P < 0.001).

Conclusions: diabetes is associated with excess mortality following hip fracture across all ages, but the excess mortality decreases with advancing age.
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http://dx.doi.org/10.1093/ageing/afz048DOI Listing
July 2019

Centenarian hip fracture patients: a nationwide population-based cohort study of 507 patients.

Acta Orthop 2019 08 18;90(4):342-347. Epub 2019 Apr 18.

d Department of Clinical Biochemistry , Hvidovre Hospital, University of Copenhagen , Hvidovre , Denmark.

Background and purpose - Several studies suggest a global increase of centenarians during the 21st century. We describe temporal trends of hip fracture incidence and mortality in this group and compare these patients with a group of younger hip fracture patients with regards to comorbidities and mortality. Patients and methods - The full study population included all hip fractures that occurred in Denmark (n = 154,047) between 1996 and 2012. Patients aged 100 or above were identified (n = 507) and hip fracture patients between the ages of 70 to 99 years (n = 124,007) were used for comparison. Data were accessed from national registries. Trends in incidence over time were analyzed using a log-linear regression model, mortality was analyzed using the Kaplan-Meier estimator and trends in mortality over time were analyzed using a log-binomial regression model to obtain relative risk estimates. Results and interpretation - The centenarian patients had fewer comorbidities than the younger comparison group, but mortality was higher at all timepoints. There was no statistically significant change in mortality over time but the incidence of hip fracture among centenarians decreased during the same time period. Our findings describe the characteristics of an emerging group of hip fracture patients and could be of use in the planning of healthcare in the years to come.
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http://dx.doi.org/10.1080/17453674.2019.1602386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7025685PMC
August 2019

Pre-fracture medication use as a predictor of 30-day mortality in hip fracture patients: an analysis of 141,201 patients.

Hip Int 2020 Jan 1;30(1):101-106. Epub 2019 Mar 1.

Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen, Denmark.

Purpose: To evaluate the predictive value of pre-fracture medication usage on 30-day mortality following a hip fracture.

Methods: Information on age, sex, fracture type, time of death and Charlson co-morbidity index (CCI) was collected from the Danish National Patient Registry on all patients above 60 years, sustaining a hip fracture during the period January 1995 to December 2013. Information on drug usage was obtained from the Danish National Prescription Database. Hazard ratios were calculated with 30-day mortality as the outcome. A univariate and 3 multivariate analyses were conducted with increasing adjustments, starting with age, sex and fracture type, adding co-morbidity and dose in the latter.

Results: 141,201 patients were included and a total of 12 drugs/drug groups were identified for analysis. Increased mortality was evident in all analyses for antiarrhythmics, beta blockers, proton pump inhibitors, loop diuretics, opioids, acetaminophen and for psycholeptics. For ACE-inhibitors, increased mortality was found in all analyses, except after adjustment for co-morbidity and dose. For thiazide diuretics, a significantly reduced mortality was evident in all but the univariate analyses while NSAIDs and statins were associated with a significantly reduced mortality in all analyses. For calcium channel blockers, an insignificant decrease was found after adjustment for dose. Further analysis showed a dose-response relationship for all drugs except ACE-inhibitors and calcium channel blockers.

Conclusion: The study shows a correlation between pre-fracture usage of certain drugs and 30 day mortality after a hip fracture.
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http://dx.doi.org/10.1177/1120700019832603DOI Listing
January 2020

How To Identify Familial Premature Myocardial Infarction: Comparing Approaches To Identify Familial Hypercholesterolemia.

J Clin Endocrinol Metab 2019 07;104(7):2657-2667

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev Ringvej, Herlev, Denmark.

Context: How best to identify families with premature myocardial infarction is unclear.

Objective: We compared approaches to identify familial premature myocardial infarction in the general population using different familial hypercholesterolemia (FH) criteria and low-density lipoprotein (LDL) cholesterol cut-points.

Design And Setting: Clinical and mutation criteria for FH and LDL cholesterol cut-points were applied for identification of familial premature myocardial infarction in 106,732 individuals from the Copenhagen General Population Study.

Results: FH criteria identified 898 (13%) cases with familial premature myocardial infarction, leaving 5856 (87%) cases undetected. The ORs for familial premature myocardial infarction, compared with the respective remainder groups, were 4.7 (95% CI, 3.7 to 6.0) for clinical FH by Dutch Lipid Clinic Network criteria, 4.4 (4.0 to 4.7) for Simon Broome criteria, 2.1 (95% CI, 1.7 to 3.6) for Make Early Diagnosis to Prevent Early Death criteria, 2.1 (95% CI, 1.4 to 3.3) for FH mutation, and 1.4 (95% CI, 1.3 to1.6) for LDL cholesterol ≥5 mmol/L (193 mg/dL). For these risk groups, the sensitivity (true positive rate) for identification of familial premature myocardial infarction were 1.3%, 13%, 1.6%, 0.9%, and 7.1%, respectively. Compared with universal screening of a similar fraction of the population, the relative increase in sensitivity for these risk groups was 3.8-fold [fraction of population examined: 0.3%, 3.3-fold (4%), 2.0-fold (0.8%), 2.0-fold (0.4%), and 1.4-fold (5.3%), respectively].

Conclusion: Criteria for FH identify a small fraction of individuals with familial premature myocardial infarction in the general population. Actively identifying families with premature myocardial infarction would be of potential preventive importance, and this study provides data that could be used to choose the best method for such family identification.
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http://dx.doi.org/10.1210/jc.2018-02261DOI Listing
July 2019

Low HDL Cholesterol and High Risk of Autoimmune Disease: Two Population-Based Cohort Studies Including 117341 Individuals.

Clin Chem 2019 05 11;65(5):644-652. Epub 2019 Feb 11.

Department of Clinical Biochemistry and

Background: HDL is quantitatively the most important lipoprotein in most species and mechanistic evidence points toward a role for HDL in normal immune function. We tested the hypothesis that concentrations of HDL cholesterol are associated with risk of autoimmune disease.

Methods: From 2 studies of the general population-the Copenhagen General Population Study and the Copenhagen City Heart study-we included 107954 and 9387 individuals with baseline measurements of HDL cholesterol. These were followed with the national Danish Patient Registry from baseline in 2003-2015 or 1991-1994 through 2017, during which time 4078 and 1101 individuals developed autoimmune disease in the 2 studies.

Results: In the Copenhagen General Population Study, compared to individuals with HDL cholesterol ≥2.0 mmol/L (77 mg/dL), the multifactorially adjusted hazard ratios for any autoimmune disease were 1.06 (95% CI, 0.94-1.19) for individuals with HDL cholesterol of 1.5-1.99 mmol/L (58-77 mg/dL), 1.18 (95% CI, 1.04-1.35) for individuals with HDL cholesterol of 1.0-1.49 mmol/L (39-58 mg/dL), and 1.84 (95% CI, 1.52-2.22) for individuals with HDL cholesterol <1.0 mmol/L (39 mg/dL) ( for trend <0.001). These results were similar when excluding events within 5 years of baseline, in women and men separately, for events at baseline, irrespective of low-grade inflammation or triglyceride concentrations, for the apolipoprotein A1 part of HDL, and for more restrictive end point definitions. Finally, the Copenhagen City Heart Study provided independent confirmation.

Conclusions: Low HDL cholesterol level is associated with high risk of autoimmune disease in individuals from the general population. Our observational findings cannot determine causality.
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http://dx.doi.org/10.1373/clinchem.2018.299636DOI Listing
May 2019

Low-Grade Inflammation in the Association between Mild-to-Moderate Hypertriglyceridemia and Risk of Acute Pancreatitis: A Study of More Than 115000 Individuals from the General Population.

Clin Chem 2019 02 5;65(2):321-332. Epub 2018 Dec 5.

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark;

Background: How mild-to-moderate hypertriglyceridemia (2-10 mmol/L; 177-886 mg/dL) potentially causes acute pancreatitis is unknown; however, cellular studies indicate that inflammation might be a driver of disease progression. We tested the hypotheses that () mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and that () the association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis depends on low-grade inflammation.

Methods: From the Copenhagen General Population Study and the Copenhagen City Heart Study, 117865 men and women 20-100+ years of age with measurements of nonfasting plasma triglycerides at baseline were followed prospectively for development of acute pancreatitis.

Results: After multivariable adjustment, a 1 mmol/L (89 mg/dL) higher nonfasting triglyceride concentration was associated with 17% (95% CI, 16%-18%, = 3 × 10) higher plasma C-reactive protein (CRP) and a 4.2% (4.0%-4.4%, = 6 × 10) higher blood leukocyte count. Higher concentrations of nonfasting triglycerides were associated almost linearly with higher risk of acute pancreatitis ( for trend = 5 × 10), with hazard ratios of 1.5 (95% CI, 0.9-2.5), 2.0 (95% CI, 1.1-3.6), 2.2 (95% CI, 1.0-4.7), 4.2 (95% CI, 1.6-11.5), and 7.7 (95% CI, 3.0-19.8) in individuals with nonfasting triglycerides of 1.00-1.99 mmol/L (89-176 mg/dL; 46% of the population), 2.00-2.99 mmol/L (177-265 mg/dL; 17%), 3.00-3.99 mmol/L (266-353 mg/dL; 6%), 4.00-4.99 mmol/L (354-442 mg/dL; 2%), and ≥5mmol/L(443 mg/dL; 2%), respectively, vs individuals with <1 mmol/L (89 mg/dL; 27%). The association with risk of acute pancreatitis appeared more pronounced in individuals with CRP of ≥1.39 mg/L ( for trend = 0.001) and leukocytes of ≥7 × 10/L ( = 2 × 10) than in those with CRP <1.39 mg/L ( = 0.03) and leukocytes <7 × 10/L ( = 0.04); however, there was no formal evidence of statistical interaction ( = 0.38 for CRP and = 0.41 for leukocytes).

Conclusions: Mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and higher risk of acute pancreatitis. The association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis is possibly partly mediated by low-grade inflammation.
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http://dx.doi.org/10.1373/clinchem.2018.294926DOI Listing
February 2019

Relationship of Familial Hypercholesterolemia and High Low-Density Lipoprotein Cholesterol to Ischemic Stroke: Copenhagen General Population Study.

Circulation 2018 08;138(6):578-589

Department of Clinical Biochemistry (S.B., C.M.M., A.V., B.G.N).

Background: Familial hypercholesterolemia (FH) is a condition with very high concentrations of low-density lipoprotein (LDL) cholesterol and high risk of ischemic heart disease including myocardial infarction. However, there is limited and contradictory information on whether FH and high LDL cholesterol per se confer high risk of ischemic stroke. We tested the hypotheses that individuals in the general population with FH and/or high LDL cholesterol have higher risk of ischemic stroke.

Methods: The associations of FH and high LDL cholesterol with ischemic stroke risk were tested in both causal, genetic, and observational analyses using 106 412 individuals from the CGPS (Copenhagen General Population Study; 2823 ischemic strokes and 3792 myocardial infarctions) and/or 10 372 individuals from the CCHS (Copenhagen City Heart Study; 945 ischemic strokes and 1142 myocardial infarctions). FH causative mutations were LDLR W23X(rs267607213), W66G(rs121908025) and W556S, and APOB R3500Q(rs5742904). A Mendelian randomization design tested whether high LDL cholesterol per se has a causal effect on ischemic stroke risk, using a combination of the FH causative mutations and common genetic variants associated with high LDL cholesterol.

Results: The cumulative incidences in individuals in the CGPS with and without FH causative mutations were similar for ischemic stroke ( P=0.50) but not for myocardial infarction ( P<0.001): at age 80 years, 4% and 7% of these individuals developed ischemic stroke and 20% and 8% myocardial infarction, with similar results in the CCHS. There was no association between clinical FH and ischemic stroke, except if personal premature ischemic heart disease was included in the clinical FH criteria. Ischemic heart disease at baseline was associated with higher ischemic stroke risk, explaining the higher ischemic stroke risk in those with high LDL cholesterol. For a 1 mmol/L higher LDL cholesterol, the genetic causal risk ratio was 1.11 (0.62-2.02) for ischemic stroke and 1.45 (1.08-1.93) for myocardial infarction.

Conclusions: FH and high LDL cholesterol did not confer an increased risk of ischemic stroke. A positive association with ischemic stroke observed for some clinical FH criteria and high LDL cholesterol appears to be due to previous ischemic heart disease, rather than to high LDL cholesterol per se.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.118.033470DOI Listing
August 2018

Is It Time for New Thinking About High-Density Lipoprotein?

Arterioscler Thromb Vasc Biol 2018 03;38(3):484-486

From the Department of Clinical Biochemistry (C.M.M., B.G.N.) and The Copenhagen General Population Study (C.M.M., B.G.N.), Herlev and Gentofte Hospital, Copenhagen University Hospital, Denmark; and Faculty of Health and Medical Sciences, University of Copenhagen, Denmark (C.M.M., B.G.N).

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http://dx.doi.org/10.1161/ATVBAHA.118.310727DOI Listing
March 2018

Temporal trends in hip fracture incidence, mortality, and morbidity in Denmark from 1999 to 2012.

Acta Orthop 2018 Apr 1;89(2):170-176. Epub 2018 Feb 1.

b Department of Clinical Biochemistry , Bispebjerg Hospital, University of Copenhagen , Denmark.

Background and purpose - While development in hip fracture incidence and mortality is well examined, none has yet looked at the temporal trends regarding prevalence of co-morbidities. Therefore we investigated changes in incidence of first hip fracture, co-morbidity prevalence, 30 day- and 1-year mortality in hip fracture patients in the Danish population during the period 1999 to 2012. Patients and methods - Patients >18 years admitted with a fractured hip in Denmark between 1996 and 2012 were identified with data for the period 1999-2012 being analyzed regarding prevalence of co-morbidities, incidence, and mortality. Results - 122,923 patients were identified. Incidence in the whole population declined but sex-specific analysis showed no changes for men. For the whole study population, 30-day and 1-year mortality remained unchanged. Age at time of first hip fracture also remained unchanged. Of the included co-morbidities a decrease in prevalence of malignancy and dementia in women was found while there was an increase in the prevalence of all remaining co-morbidities, except hemi- or paraplegia for both sexes, rheumatic diseases for women, and for men diabetes with complications, myocardial infarction, AIDS/HIV, and malignancy. Interpretation - While hip fracture incidence declined for women it was unchanged for men; likewise, 30-day and 1-year mortality rates together with age at first fracture remained unchanged. When these results are compared with the relatively large increase in the prevalence of co-morbidities, it does not seem likely that the increased disease burden is affecting either the incidence or the mortality.
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http://dx.doi.org/10.1080/17453674.2018.1428436DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5901514PMC
April 2018

U-shaped relationship of HDL and risk of infectious disease: two prospective population-based cohort studies.

Eur Heart J 2018 04;39(14):1181-1190

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark.

Aims: Preclinical evidence has indicated that HDL may play an important role in the immune system; however, very little is known about the role of HDL in the immune system in humans. We tested the hypothesis that low and high concentrations of HDL cholesterol are associated with risk of infectious disease in the general population.

Methods And Results: We included 97 166 individuals from the Copenhagen General Population Study and 9387 from the Copenhagen City Heart Study with measurements of HDL cholesterol at baseline. The primary endpoint was any infectious disease requiring hospital admission, ascertained in the Danish health registries from baseline in 2003-13 or 1991-94 through 2014; 9% and 31% of individuals in the two studies experienced one or more infectious disease events. Using restricted cubic splines, there was a U-shaped association between concentrations of HDL cholesterol and risk of any infection. Following multifactorial adjustment, individuals with HDL cholesterol below 0.8 mmol/L (31 mg/dL) and above 2.6 mmol/L (100 mg/dL) had hazard ratios for any infection of 1.75 (95% confidence interval 1.31-2.34) and 1.43 (1.16-1.76), compared to those with HDL cholesterol of 2.2-2.3 mmol/L (85-95 mg/dL). In the Copenhagen City Heart Study, corresponding hazard ratios for any infection were 2.00 (1.16-3.43) and 1.13 (0.80-1.60).

Conclusion: Low and high HDL cholesterol concentrations found in 21% and 8% of individuals were associated with higher risk of infectious disease in the general population. These findings do not necessarily indicate causality.
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http://dx.doi.org/10.1093/eurheartj/ehx665DOI Listing
April 2018

Unmet need for primary prevention in individuals with hypertriglyceridaemia not eligible for statin therapy according to European Society of Cardiology/European Atherosclerosis Society guidelines: a contemporary population-based study.

Eur Heart J 2018 02;39(7):610-619

Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark.

Aims: To identify individuals at high risk of atherosclerotic cardiovascular disease (ASCVD), who are not definite statin eligible according to the 2016 European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) guidelines, based on high concentrations of plasma triglycerides.

Methods And Results: From the Copenhagen General Population Study (2003-2015) 58 547 individuals aged 40-65 and free of ASCVD, diabetes, and statin use at baseline were included. Of these, 14% were definite statin eligible, 7% were not eligible and had triglycerides ≥3.0 mmol/L (264 mg/dL), and 79% were not statin eligible and had triglycerides <3.0 mmol/L (264 mg/dL). During 456 057 person-years of follow-up, 1770 individuals experienced a major adverse cardiovascular event (MACE) and 734 experienced a myocardial infarction (MI). The cumulative incidences of MACE at age 70 were 8.1% (95% confidence interval 7.3-8.9%) and 14.6% (12.6-16.8%) in statin non-eligible individuals with triglycerides <3.0 mmol/L (264 mg/dL) and ≥3.0 mmol/L (264 mg/dL), and 16.5% (14.0-19.3%) in statin eligible individuals. Corresponding cumulative incidences of MI were 3.0% (2.7-3.3%), 7.8% (6.4-9.5%), and 7.1% (5.9-8.4%), respectively. The estimated 10-year risks of MACE were 2.8% (2.6-3.0%) and 5.7% (4.9-6.6%) in statin non-eligible individuals with triglycerides <3.0 mmol/L (264 mg/dL) and ≥3.0 mmol/L (264 mg/dL), and 7.6% (6.9-8.3%) in statin eligible individuals; the median age in these three groups were 51, 51, and 60 years, respectively. Corresponding risks of MI were 1.0% (0.9-1.1%), 3.0% (2.4-3.7%), and 3.3% (2.8-3.7%), respectively.

Conclusion: Statin non-eligible individuals with triglycerides ≥3.0 mmol/L (264 mg/dL) had risk of ASCVD similar to statin eligible individuals, defined according to the 2016 ESC/EAS guidelines. This illustrates an unmet need for primary prevention, calling for expansion of guidelines on statin eligibility, and the potential for placebo-controlled randomized clinical trials in individuals with hypertriglyceridaemia.
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http://dx.doi.org/10.1093/eurheartj/ehx659DOI Listing
February 2018

Extreme high high-density lipoprotein cholesterol is paradoxically associated with high mortality in men and women: two prospective cohort studies.

Eur Heart J 2017 Aug;38(32):2478-2486

Department of Clinical Biochemistry.

Aims: High-density lipoprotein (HDL) cholesterol concentrations are inversely associated with cardiovascular disease and mortality across a range of concentrations, but genetic evidence suggest that extreme high concentrations may paradoxically lead to more cardiovascular disease. We tested the hypothesis that extreme high concentrations of HDL cholesterol are associated with high all-cause mortality in men and women.

Methods And Results: A total of 52 268 men and 64 240 women were included from the two prospective population-based studies, the Copenhagen City Heart Study and the Copenhagen General Population Study. During 745 452 person-years of follow-up, number of deaths from any cause were 5619 (mortality rate, 17.1/1000 person-years (95% confidence interval (CI): 16.7-17.6)) in men and 5059 (mortality rate, 12.1/1000 person-years (11.8-12.4)) in women. The association between HDL cholesterol concentrations and all-cause mortality was U-shaped for both men and women, with both extreme high and low concentrations being associated with high all-cause mortality risk. The concentration of HDL cholesterol associated with the lowest all-cause mortality was 1.9 mmol/L (95% CI: 1.4-2.0) (73 mg/dL (54-77)) in men and 2.4 mmol/L (1.8-2.5) (93 mg/dL (69-97)) in women. When compared with the groups with the lowest risk, the multifactorially adjusted hazard ratios for all-cause mortality were 1.36 (95% CI: 1.09-1.70) for men with HDL cholesterol of 2.5-2.99 mmol/L (97-115 mg/dL) and 2.06 (1.44-2.95) for men with HDL cholesterol ≥3.0 mmol/L (116 mg/dL). For women, corresponding hazard ratios were 1.10 (0.83-1.46) for HDL cholesterol of 3.0-3.49 mmol/L (116-134 mg/dL) and 1.68 (1.09-2.58) for HDL cholesterol ≥3.5 mmol/L (135 mg/dL).

Conclusion: Men and women in the general population with extreme high HDL cholesterol paradoxically have high all-cause mortality. These findings need confirmation in other studies.
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http://dx.doi.org/10.1093/eurheartj/ehx163DOI Listing
August 2017

Low Levels of Hemoglobin at Admission Are Associated With Increased 30-Day Mortality in Patients With Hip Fracture.

Geriatr Orthop Surg Rehabil 2016 Sep 17;7(3):115-20. Epub 2016 May 17.

Department of Orthopaedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark.

Introduction: Previous smaller studies suggest that anemia is a risk factor for mortality in patients with hip fracture. The purpose of this investigation was to assess the correlation between hemoglobin at admission with 30-day mortality following a hip fracture in a large-scale study.

Patients And Methods: From January 1996 to December 2012, all patients with hip fracture (>60 years of age) admitted to Bispebjerg Hospital, Copenhagen, were identified from a local hip fracture database. We excluded conservatively treated patients and patients who died preoperatively.

Results: Seven thousand four hundred twenty-one consecutive patients with hip fracture were identified. Of those 7319 had a hemoglobin measurement on admission and were thus eligible for further analysis. Mean hemoglobin for patients alive at 30 days was 7.6 (standard deviation [SD]: 1.0) and for deceased patients 7.4 (SD: 1.1), P < .0001. Mean age was 82.6 years (SD: 8.5), and 76.5% of the population were female (Nfemales = 5600). The 30-day mortality decreases for every increase in hemoglobin of 1.0 mmol/L in a univariate analysis (P < .0001). The hazard ratio (HR) with 95% confidence interval (CI) for 30-day mortality in patients with anemia (<7.3 mmol/L for females and <8.3 mmol/L for males; Nanemic = 3235) was 1.66 (CI: 1.43-1.91, P < .0001). Adjusting for age, type of fracture, gender, and comorbidities (Charlson score) slightly attenuated the risk estimate (HR: 1.21, CI: 1.03-1.41, P = .02).

Conclusion: This study demonstrates increased 30-day mortality in patients with low hemoglobin at admission, even after adjusting for comorbidities.
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http://dx.doi.org/10.1177/2151458516647989DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4976734PMC
September 2016

Testing of Badminton-Specific Endurance.

J Strength Cond Res 2016 Sep;30(9):2582-90

1Department of Nutrition, Exercise, and Sports, University of Copenhagen; Stenhus Gymnasium & HF, Holbæk, Denmark; and 2Department of Sport: Test and Knowledge Center Stenhus Gymnasium and HF, Holbæk, Denmark.

Madsen, CM, Højlyng, M, and Nybo, L. Testing of badminton-specific endurance. J Strength Cond Res 30(9): 2582-2590, 2016-In the present study, a novel intermittent badminton endurance (B-ENDURANCE) test was developed and tested in elite (n = 17) and skilled (n = 9) badminton players and in age-matched physically active men (nonbadminton players; n = 8). In addition, B-ENDURANCE test-retest reproducibility was evaluated in 9 badminton players. The B-ENDURANCE test is an incremental test where each level consists of repeated sequences of badminton-specific actions toward the 4 corners of the court. The subject starts in the center of the court in front of a computer screen and within each sequence, he must, in a randomized order, complete 8 actions as dictated by the computer, providing the audiovisual input and verifying that the appropriate sensor is activated within the allocated time. Recovery time between each sequence is 10 seconds throughout the test, but the time to complete each sequence is gradually decreased until the subjects cannot follow the dictated tempo. The B-ENDURANCE test performance for elite players was better (p ≤ 0.05) compared with the skilled players and nonbadminton players. In addition, the B-ENDURANCE test performance correlated (r = 0.8 and p < 0.0001) with elite players' national single rankings. Test-retest coefficient of variation was 7.9% between the first 2 trials (i.e., without a familiarization trial) but reduced to 2.5% when comparing the second and third trials. In conclusion, the B-ENDURANCE test is relevant for the evaluation of badminton-specific endurance but at least 1 familiarization trial is recommended if the test is used for evaluation of longitudinal changes, e.g., tracking training effects.
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http://dx.doi.org/10.1519/JSC.0000000000001350DOI Listing
September 2016

Novel speed test for evaluation of badminton-specific movements.

J Strength Cond Res 2015 May;29(5):1203-10

Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.

In this study, we developed a novel badminton-specific speed test (BST). The test was designed to mimic match play. The test starts in the center of the court and consists of 5 maximal actions to sensors located in each of the 4 corners of the court. The 20 actions are performed in randomized order as dictated by computer screen shots displayed 1 second after completion of the previous action. We assessed day-to-day variation in elite players, and specificity of the test was evaluated by comparing 30-m sprint performance and time to complete the BST in 20 elite players, 21 skilled players, and 20 age-matched physical active subjects (non-badminton players). Sprint performance was similar across groups, whereas the elite players were significantly (p ≤ 0.05) faster in the BST (total test time: 32.3 ± 1.1 seconds; average: 1.6 seconds per action) than the skilled (34.1 ± 2.0 seconds) and non-badminton players (35.7 ± 1.7 seconds). Day-to-day coefficient of variation (CV) of the BST was 0.7% for the elite players, whereas CV for repeated tests on the same day was 1.7% for elite, 2.6% for skilled, and 2.5% for non-badminton players. On this basis, we suggest that the BST may be valuable for evaluation of short-term maximal movement speed in badminton players. Thus, the BST seems to be sport specific, as it may discriminate between groups (elite, less trained players, and non-badminton players) with similar sprinting performance, and the low test-retest variation may allow for using the BST to evaluate longitudinal changes, for example, training effects or seasonal variations.
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http://dx.doi.org/10.1519/JSC.0000000000000635DOI Listing
May 2015

Small molecule antagonism of oxysterol-induced Epstein-Barr virus induced gene 2 (EBI2) activation.

FEBS Open Bio 2013 19;3:156-60. Epub 2013 Feb 19.

Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark.

The Epstein-Barr virus induced gene 2 (EBI2) was recently identified as the first oxysterol-activated 7TM receptor. EBI2 is essential for B cell trafficking within lymphoid tissues and thus the humoral immune response in general. Here we characterize the antagonism of the non-peptide molecule GSK682753A, which blocks oxysterol-induced G-protein activation, β-arrestin recruitment and B-cell chemotaxis. We furthermore demonstrate that activation triggers pertussis toxin-sensitive MAP kinase phosphorylation, which is also inhibited by GSK682753A. Thus, EBI2 signalling in B cells mediates key phenotypic functions via signalling pathways amenable to manipulation providing additional therapeutic options for inhibiting EBI2 activity.
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http://dx.doi.org/10.1016/j.fob.2013.02.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3668520PMC
June 2013

Molecular characterization of oxysterol binding to the Epstein-Barr virus-induced gene 2 (GPR183).

J Biol Chem 2012 Oct 8;287(42):35470-35483. Epub 2012 Aug 8.

Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark. Electronic address:

Oxysterols are oxygenated cholesterol derivates that are emerging as a physiologically important group of molecules. Although they regulate a range of cellular processes, only few oxysterol-binding effector proteins have been identified, and the knowledge of their binding mode is limited. Recently, the family of G protein-coupled seven transmembrane-spanning receptors (7TM receptors) was added to this group. Specifically, the Epstein-Barr virus-induced gene 2 (EBI2 or GPR183) was shown to be activated by several oxysterols, most potently by 7α,25-dihydroxycholesterol (7α,25-OHC). Nothing is known about the binding mode, however. Using mutational analysis, we identify here four key residues for 7α,25-OHC binding: Arg-87 in TM-II (position II:20/2.60), Tyr-112 and Tyr-116 (positions III:09/3.33 and III:13/3.37) in TM-III, and Tyr-260 in TM-VI (position VI:16/6.51). Substituting these residues with Ala and/or Phe results in a severe decrease in agonist binding and receptor activation. Docking simulations suggest that Tyr-116 interacts with the 3β-OH group in the agonist, Tyr-260 with the 7α-OH group, and Arg-87, either directly or indirectly, with the 25-OH group, although nearby residues likely also contribute. In addition, Tyr-112 is involved in 7α,25-OHC binding but via hydrophobic interactions. Finally, we show that II:20/2.60 constitutes an important residue for ligand binding in receptors carrying a positively charged residue at this position. This group is dominated by lipid- and nucleotide-activated receptors, here exemplified by the CysLTs, P2Y12, and P2Y14. In conclusion, we present the first molecular characterization of oxysterol binding to a 7TM receptor and identify position II:20/2.60 as a generally important residue for ligand binding in certain 7TM receptors.
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http://dx.doi.org/10.1074/jbc.M112.387894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3471686PMC
October 2012