| 1. |
- Bergström, Göran, 1964, et al.
(författare)
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Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population
- 2021
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Ingår i: Circulation. - Philadelphia : American Heart Association. - 0009-7322 .- 1524-4539. ; 144:12, s. 916-929
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Tidskriftsartikel (refereegranskat)abstract
- Background: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population.Methods: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data.Results: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population.Conclusions: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.
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| 2. |
- Bergström, Göran, et al.
(författare)
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Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population
- 2021
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Ingår i: Circulation. - : Wolters Kluwer. - 0009-7322 .- 1524-4539. ; 144:12, s. 916-929
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Tidskriftsartikel (refereegranskat)abstract
- Background: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population.Methods: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data.Results: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population.Conclusions: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.
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| 3. |
- Björnson, Elias, 1988
(författare)
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Lipoproteins in the postprandial state: Studies on the metabolism of triglyceride-rich lipoproteins using multicompartmental models
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lipoproteins are lipid-containing spherical particles that circulate in the human blood stream. The reason for their intense study over the decades is their ability to cause atherosclerosis1. Atherosclerotic cardiovascular disease (ASCVD) remains as the single largest cause of death worldwide; and here in Sweden, around a third of all deaths can be attributed to the category: diseases of the circulatory system2. The strength of evidence that low-density lipoproteins (LDL) cause ASCVD is very high. In recent years evidence has emerged indicating that so-called triglyceride-rich lipoproteins (TRLs) also contribute causally to atherosclerosis3. The two sources of TRLs in the human circulation are the liver – which produces lipoproteins continuously, and the intestine – which produces lipoproteins in response to a meal. The liver-derived particles contain a structural surface protein called apolipoprotein B100 (apoB100) whereas particles from the intestine contain apolipoprotein B48 (apoB48). TRLs can also be further classified based on density into the following fractions: intermediate-density lipoprotein (IDL), very low-density lipoprotein 2 (VLDL2), very low-density lipoprotein 1 (VLDL1) and lastly the chylomicron (CM) fraction. Lipoproteins are studied in many ways, both in humans and in model organisms. In the current thesis I, study human lipoproteins in vivo with the help of multicompartmental modelling in conjunction with specifically designed metabolic studies involving stable isotopes. This enables quantification of the fluxes of lipoproteins as opposed to quantification of concentrations only. I developed a model able to study the postprandial, non-steady state, metabolism of both apoB48- and apoB100 containing lipoproteins. The model was primarily designed to study TRLs but was later adapted to also encompass LDL. After developing the model, it was first implemented for the purpose of studying whether the metabolism of TRLs differed across the range of subjects with low-to-high TRL levels. ApoB48 was found to track the metabolism of apoB100 which revealed a more complex picture of the state of hypertriglyceridemia (high levels of TRLs) with postprandial excursions of particles overlayered on a baseline steady-state level. Second, the model was implemented to study the effects of the antidiabetic drug liraglutide. We found that chylomicron secretion was specifically affected by liraglutide, an effect that was likely independent from the improvements in insulin sensitivity induced by the drug. Lastly, we implemented the expanded model to study the effects of the LDL-cholesterol lowering drug evolocumab. We found that evolocumab mostly affected apoB100-containing lipoproteins. Particles in the VLDL1 fraction remained unaffected but VLDL2, IDL and LDL concentrations were decreased with the largest effect size seen for LDL (around 80 % reduction). We further found evidence for the existence of two distinct LDL species with differing kinetic properties, that were differentially affected by evolocumab. In conclusion, here I present a new comprehensive multicompartmental model of lipoprotein metabolism. The model is designed to study apoB100- and apoB48 containing lipoproteins in the postprandial state. The model is used in the current thesis to study TRLs in hypertriglyceridemia and to study the effect of drugs on both TRLs and LDLs. The higher purpose for these studies is to add to the body of evidence for the role of lipoproteins in heart disease.
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| 4. |
- Bosley, J. R., et al.
(författare)
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Informing Pharmacokinetic Models With Physiological Data: Oral Population Modeling of L-Serine in Humans
- 2021
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Ingår i: Frontiers in Pharmacology. - : Frontiers Media SA. - 1663-9812. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- To determine how to set optimal oral L-serine (serine) dose levels for a clinical trial, existing literature was surveyed. Data sufficient to set the dose was inadequate, and so an (n = 10) phase I-A calibration trial was performed, administering serine with and without other oral agents. We analyzed the trial and the literature data using pharmacokinetic (PK) modeling and statistical analysis. The therapeutic goal is to modulate specific serine-related metabolic pathways in the liver using the lowest possible dose which gives the desired effect since the upper bound was expected to be limited by toxicity. A standard PK approach, in which a common model structure was selected using a fit to data, yielded a model with a single central compartment corresponding to plasma, clearance from that compartment, and an endogenous source of serine. To improve conditioning, a parametric structure was changed to estimate ratios (bioavailability over volume, for example). Model fit quality was improved and the uncertainty in estimated parameters was reduced. Because of the particular interest in the fate of serine, the model was used to estimate whether serine is consumed in the gut, absorbed by the liver, or entered the blood in either a free state, or in a protein- or tissue-bound state that is not measured by our assay. The PK model structure was set up to represent relevant physiology, and this quantitative systems biology approach allowed a broader set of physiological data to be used to narrow parameter and prediction confidence intervals, and to better understand the biological meaning of the data. The model results allowed us to determine the optimal human dose for future trials, including a trial design component including IV and tracer studies. A key contribution is that we were able to use human physiological data from the literature to inform the PK model and to set reasonable bounds on parameters, and to improve model conditioning. Leveraging literature data produced a more predictive, useful model.
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| 5. |
- Gasim Elsied, Anwar Ali, et al.
(författare)
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Sacubitril/valsartan decreases mortality in the rat model of the isoprenaline-induced takotsubo-like syndrome
- 2021
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Ingår i: ESC Heart Failure. - : Wiley. - 2055-5822. ; 8:5, s. 4130-4138
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Tidskriftsartikel (refereegranskat)abstract
- Aims Takotsubo syndrome (TTS) is an acute potentially reversible cardiac syndrome characterized by variable regional myocardial akinesia that cannot be attributed to a culprit coronary artery occlusion. TTS is an important differential diagnosis of acute heart failure where brain natriuretic peptides are elevated. Sacubitril/valsartan is a novel and effective pharmacological agent for the treatment of patients with heart failure. Our aim was to explore whether treatment with sacubitril/valsartan could prevent isoprenaline-induced takotsubo-like phenotype in rats. Methods and results A total number of 186 Sprague-Dawley male rats were randomized to receive pretreatment with water (CONTROL, n = 62), valsartan (VAL, n = 62), or sacubitril/valsartan (SAC/VAL, n = 62) before receiving isoprenaline for induction of TTS. We recorded heart rate and blood pressure invasively. Cardiac morphology and function were evaluated by high-resolution echocardiography 90 min after the administration of isoprenaline. We documented the survival rate at the time of echocardiography. Compared with the CONTROL group, the SAC/VAL group had less pronounced TTS-like cardiac dysfunction and lower mortality rate, while the VAL group did not differ. Heart rate and blood pressure were not significantly different between the groups. Analysis of cardiac lipids was performed with mass spectrometry. The VAL and SAC/VAL groups had significantly higher levels of lysophosphatidylcholine (LPC), in particular LPC 18:1 and LPC 16:0. Conclusions Pretreatment with sacubitril/valsartan but not with valsartan reduces mortality and attenuates isoprenaline-induced apical akinesia in the TTS-like model in rats. Sacubitril/valsartan could be a potential treatment option in patients with TTS in humans.
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| 6. |
- Gummesson, Anders, 1973, et al.
(författare)
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Longitudinal plasma protein profiling of newly diagnosed type 2 diabetes
- 2021
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Ingår i: EBioMedicine. - : Elsevier B.V.. - 2352-3964. ; 63
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Tidskriftsartikel (refereegranskat)abstract
- Background: Comprehensive proteomics profiling may offer new insights into the dysregulated metabolic milieu of type 2 diabetes, and in the future, serve as a useful tool for personalized medicine. This calls for a better understanding of circulating protein patterns at the early stage of type 2 diabetes as well as the dynamics of protein patterns during changes in metabolic status. Methods: To elucidate the systemic alterations in early-stage diabetes and to investigate the effects on the proteome during metabolic improvement, we measured 974 circulating proteins in 52 newly diagnosed, treatment-naïve type 2 diabetes subjects at baseline and after 1 and 3 months of guideline-based diabetes treatment, while comparing their protein profiles to that of 94 subjects without diabetes. Findings: Early stage type 2 diabetes was associated with distinct protein patterns, reflecting key metabolic syndrome features including insulin resistance, adiposity, hyperglycemia and liver steatosis. The protein profiles at baseline were attenuated during guideline-based diabetes treatment and several plasma proteins associated with metformin medication independently of metabolic variables, such as circulating EPCAM. Interpretation: The results advance our knowledge about the biochemical manifestations of type 2 diabetes and suggest that comprehensive protein profiling may serve as a useful tool for metabolic phenotyping and for elucidating the biological effects of diabetes treatments. Funding: This work was supported by the Swedish Heart and Lung Foundation, the Swedish Research Council, the Erling Persson Foundation, the Knut and Alice Wallenberg Foundation, and the Swedish state under the agreement between the Swedish government and the county councils (ALF-agreement).
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| 7. |
- Molnar, David, et al.
(författare)
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Artificial intelligence based automatic quantification of epicardial adipose tissue suitable for large scale population studies
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- To develop a fully automatic model capable of reliably quantifying epicardial adipose tissue (EAT) volumes and attenuation in large scale population studies to investigate their relation to markers of cardiometabolic risk. Non-contrast cardiac CT images from the SCAPIS study were used to train and test a convolutional neural network based model to quantify EAT by: segmenting the pericardium, suppressing noise-induced artifacts in the heart chambers, and, if image sets were incomplete, imputing missing EAT volumes. The model achieved a mean Dice coefficient of 0.90 when tested against expert manual segmentations on 25 image sets. Tested on 1400 image sets, the model successfully segmented 99.4% of the cases. Automatic imputation of missing EAT volumes had an error of less than 3.1% with up to 20% of the slices in image sets missing. The most important predictors of EAT volumes were weight and waist, while EAT attenuation was predicted mainly by EAT volume. A model with excellent performance, capable of fully automatic handling of the most common challenges in large scale EAT quantification has been developed. In studies of the importance of EAT in disease development, the strong co-variation with anthropometric measures needs to be carefully considered.
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| 8. |
- Taskinen, Marja-Riitta, et al.
(författare)
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Effects of Evolocumab on the Postprandial Kinetics of Apo (Apolipoprotein) B100- and B48-Containing Lipoproteins in Subjects With Type 2 Diabetes.
- 2021
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Ingår i: Arteriosclerosis, thrombosis, and vascular biology. - 1524-4636.
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Tidskriftsartikel (refereegranskat)abstract
- Increased risk of atherosclerotic cardiovascular disease in subjects with type 2 diabetes is linked to elevated levels of triglyceride-rich lipoproteins and their remnants. The metabolic effects of PCSK9 (proprotein convertase subtilisin/kexin 9) inhibitors on this dyslipidemia were investigated using stable-isotope-labeled tracers. Approach and Results: Triglyceride transport and the metabolism of apos (apolipoproteins) B48, B100, C-III, and E after a fat-rich meal were investigated before and on evolocumab treatment in 13 subjects with type 2 diabetes. Kinetic parameters were determined for the following: apoB48 in chylomicrons; triglyceride in VLDL1 (very low-density lipoprotein) and VLDL2; and apoB100 in VLDL1, VLDL2, IDL (intermediate-density lipoprotein), and LDL (low-density lipoprotein). Evolocumab did not alter the kinetics of apoB48 in chylomicrons or apoB100 or triglyceride in VLDL1. In contrast, the fractional catabolic rates of VLDL2-apoB100 and VLDL2-triglyceride were both increased by about 45%, which led to a 28% fall in the VLDL2 plasma level. LDL-apoB100 was markedly reduced by evolocumab, which was linked to metabolic heterogeneity in this fraction. Evolocumab increased clearance of the more rapidly metabolized LDL by 61% and decreased production of the more slowly cleared LDL by 75%. ApoC-III kinetics were not altered by evolocumab, but the apoE fractional catabolic rates increased by 45% and the apoE plasma level fell by 33%. The apoE fractional catabolic rates was associated with the decrease in VLDL2- and IDL-apoB100 concentrations.Evolocumab had only minor effects on lipoproteins that are involved in triglyceride transport (chylomicrons and VLDL1) but, in contrast, had a profound impact on lipoproteins that carry cholesterol (VLDL2, IDL, LDL). Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02948777.
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| 9. |
- Taskinen, M. R., et al.
(författare)
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Effects of liraglutide on the metabolism of triglyceride-rich lipoproteins in type 2 diabetes
- 2021
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Ingår i: Diabetes Obesity & Metabolism. - : Wiley. - 1462-8902 .- 1463-1326. ; 23:5, s. 1191-1201
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To elucidate the impact of liraglutide on the kinetics of apolipoprotein (apo) B48- and apoB100-containing triglyceride-rich lipoproteins in subjects with type 2 diabetes (T2D) after a single fat-rich meal. Materials and Methods: Subjects with T2D were included in a study to investigate postprandial apoB48 and apoB100 metabolism before and after 16 weeks on 1.8 mg/day liraglutide (n = 14) or placebo (n = 4). Stable isotope tracer and compartmental modelling techniques were used to determine the impact of liraglutide on chylomicron and very low-density lipoprotein (VLDL) production and clearance after a single fat-rich meal. Results: Liraglutide reduced apoB48 synthesis in chylomicrons by 60% (p < .0001) and increased the triglyceride/apoB48 ratio (i.e. the size) of chylomicrons (p < .001). Direct clearance of chylomicrons, a quantitatively significant pathway pretreatment, decreased by 90% on liraglutide (p < .001). Liraglutide also reduced VLDL1-triglyceride secretion (p = .017) in parallel with reduced liver fat. Chylomicron-apoB48 production and particle size were related to insulin sensitivity (p = .015 and p < .001, respectively), but these associations were perturbed by liraglutide. Conclusions: In a physiologically relevant setting that mirrored regular feeding in subjects with T2D, liraglutide promoted potentially beneficial changes on postprandial apoB48 metabolism. Using our data in an integrated metabolic model, we describe how the action of liraglutide in T2D on chylomicron and VLDL kinetics could lead to decreased generation of remnant lipoproteins.
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