| 1. |
- Good, Elin, 1983-
(författare)
-
Interrogating Atherosclerotic Plaque Biology Through Responses to Cardiovascular Risk Management and Imaging
- 2023
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Atherosclerosis causes more deaths than any other disease worldwide, and the cause of death is most commonly a rupture of a vulnerable atherosclerotic plaque, resulting in a thrombotic event in the heart or brain. The major risk factors for plaque progression are well known, but all the mechanisms that drive atherosclerotic plaques towards catastrophic events are not yet fully elucidated. This thesis revolves around the atherosclerotic plaque; how plaques can be analysed using cardiovascular magnetic resonance imaging and the study of biological responses to cardiovascular risk management. In Study I we interrogated the quality of cardiovascular risk management in patients diagnosed with high-grade carotid stenosis and found that cardiovascular risk management was deficient in all aspects, despite the very high risk for events in these patients. Thus, we designed the next two studies to address the unmet clinical need for improved cardiovascular risk management in patients with carotid atherosclerosis while at the same time asking mechanistic questions about the effect of this approach on lymphocyte phenotypes (Study II) and on plaque composition (Study III). In Study II, the effect of cardiovascular risk management on Natural Killer cell, Natural Killer T cell and T lymphocyte subpopulations were studied in patients with carotid atherosclerosis. Our results show a polarisation away from a senescent phenotype towards more naïve i.e., juvenile cell types suggesting a transition towards a possibly less pro-inflammatory lymphocyte profile. In Study III, we applied a newly developed quantitative Dixon MRI technique to the quantification of lipid rich necrotic core and hemorrhage inside atherosclerotic plaques. Employing this technique, we explored the relationships between these high-risk plaque compositional features and circulating lipoproteins as they changed over time in response to cardiovascular risk management. In the current study there was no evidence for such a linear relationship. To further study the associations between inflammation and quantitative plaque measurements we explored in Study IV the relationship between inflammation in atherosclerotic plaques as measured by 18F-FDG uptake and features of high-risk plaque as measured by quantitative Dixon MRI. To facilitate the use of carotid MRI in larger cohorts we developed in Study V a technique for the segmentation of the carotid artery using supervised machine learning. Taken together these studies describe the importance of cardiovascular risk management, the complexity of atherosclerotic plaque biology and they propose new strategies for quantitative plaque imaging.
|
|
| 2. |
- Befekadu Wodajo, Rahel, 1968-
(författare)
-
Analysis of new biomarkers and their kinetics in connection with ST-elevation myocardial infarction and percutaneous coronary intervention
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis studies different biomarkers in a cohort of patients suffering from ST-elevation myocardial infarction (STEMI) who underwent Percutaneous coronary intervention (PCI) in Örebro in 2011-2012. Blood samples were collected at three time points, at the arrival at the hospital, 1-3 days after PCI and for a smaller group of patients also 3 months after PCI. The study is a sub-study of the TASTE study, so half of the patients were also randomized to thrombus aspiration in conjunction with their PCI. For all patients, it was also recorded whether the culprit coronary vessel was totally occluded or partially patent. In total, there are samples from 165 patients, but not all markers have been measured in all patients, and 3-month samples are only available from those who had their follow-up in Örebro. The plasma levels of the biomarkers have also been measured in plasma from blood donors for comparison. In March 2019, a follow-up was made of the patients' survival, and the time of death was noted in cases where this had occurred.The markers studied are the lysosome protein Cathepsin S (Cat-S), the platelet granule protein thrombospondin 1 (TSP-1), the pentraxins C-reactive protein (CRP) and pentraxin 3 (PTX3), the endopeptidase neprilysin, the soluble forms of TNF-receptor 1 and 2 (sTNFR1 and sTNFR2), markers showing activation of the lectin pathway for complement activation (MASP-1/AT, MASP-1/C1-INH, MASP-2/C1-INH, MASP-2/AT) and common activation markers for complement activation (C3a and sC5b-9).In summary, the thesis shows that the plasma levels of all markers, except neprilysin and sC5b-9, are elevated at the time of arrival compared to healthy blood donors. Neprilysin is at the same level, and sC5b-9 is lower compared to blood donors. 1-3 days after PCI, the levels for CRP, sTNFR1 and sC5b-9 have risen strongly (>50%) compared to the levels at arrival. MASP-1/AT and MASP-2/AT have fallen moderately (about 50%), Cat-S and TSP-1 have decreased strongly, while the remaining markers are relatively similar to the levels at arrival (± 25%). The levels for CRP, PTX3, sTNFR1, sTNFR2 and neprilysin decreased even further between 1-3 days and 3 months, sC5b-9 rises slightly while the other markers remain at roughly the same levels. At 3 months, most markers still show higher levels compared to corresponding levels in blood donors, only MASP-2/C1-INH has the same level, while neprilysin is slightly lower and TSP-1 much lower compared to blood donors (the latter presumably an effect of ongoing medication with platelet inhibitors in the patients). No relevant differences were observed between patients with and without thrombus aspiration, and few differences were seen between patients with occluded or partially patent vessels. This may indicate that these factors were of minor importance for the levels of the analyzed markers. In contrast, analysis of survival showed that individuals with plasma levels above the median value for PTX3, sTNFR1 and sTNFR2 at admission and/or at 1-3 days had a significantly increased mortality compared to those with levels below the median value, which indicates that these markers could be interesting for further studies in a material where also analysis of possible interfering factors can be implemented.
|
|
| 3. |
- Slind Olsen, Renate
(författare)
-
Circulating and genetic factors in colorectal cancer : Potential factors for establishing prognosis?
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Colorectal cancer (CRC) is defined as a cancer appearing in the colon or in the rectum. In Sweden, ~ 6300 individuals were diagnosed with the disease in 2014 and ~ 2550 individuals diagnosed with CRC die each year due to their cancer. Surgery is the main treatment option of CRC and a survival rate of ~ 10 % is estimated if distant metastases have developed. It is therefore of importance to find factors that may be useful together with tumour, node, metastasis (TNM) stage to establish early CRC diagnosis, prognosis and follow-up of CRC patients. The aim of this thesis was to study the possible association of CD93, PLA2G4C, PDGF-D and inflammatory cytokines with CRC disease progression.In a prospective study approach CD93 and PLA2G4C single nucleotide polymorphisms (SNPs) were of potential importance in CRC prognosis.The T/T genotype of CD93 was associated with an increased CD93 expression in CRC tissue. Further, CRC patients carrying this genotype were associated with disseminated CRC at diagnosis and a lower recurrence-free survival after surgery. The A allele of a SNP of PLA2G4C was a stronger predictor for CRC-specific mortality than the conventional risk factors used in the clinic for selection of TNM stage II patients for adjuvant treatment. This indicates that the T/T genotype of CD93 and the A allele of PLA2G4C may be potential genetic factors related to disease severity and spread. Furthermore, they distinguish CRC patients that may benefit from a more comprehensive follow-up and adjuvant treatment.To study the putative involvement of PDGF-D in CRC the effects of PDGF-D signalling was studied in vitro. PDGF-D signalling altered the expression of genes of importance in CRC carcinogenesis and proliferation which was blocked by imatinib, a tyrosine kinase inhibitor. This indicates that PDGF-D signalling may be an important pathway in CRC progression and a potential target in CRC treatment.The analysis of various inflammatory cytokines in plasma at diagnosis showed an association between high levels and increased total- or CRC-specific mortality two years after surgery. High levels of CCL1 and CCL24 was the only cytokines strongly correlated with a worse CRC prognosis after statistical adjustments and may be of interest for further evaluation.In conclusion, this thesis presents circulating and genetic factors such as CD93, PLA2G4C, PDGF-D, CCL1 and CCL24 that may be of importance in CRC progression and may be of clinical value together with TNM stage in establishing prognosis.
|
|
| 4. |
- Vorkapić, Emina, 1987-
(författare)
-
Targeting vascular remodeling in abdominal aortic aneurysm : To identify novel treatment strategies and drug candidates
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Abdominal aortic aneurysm (AAA) is a degenerative weakening of the aortic wall, mainly affecting elderly men with a prevalence of 4.4-7.7 %. AAA is characterized by medial and adventitial inflammatory cell infiltration associated with vascular remodeling of the extracellular matrix proteins such as collagen and elastin and with phenotypic modulation and loss of vascular smooth muscle cells (VSMCs). Although much research has been performed, the precise cellular and molecular pathways behind these processes are still poorly understood. The overall aim of this thesis was to target signaling pathways that affect vascular remodeling of AAA to potentially identify novel strategies and drug candidates for future treatment of aneurysmal diseases. In order to develop our understanding of the pathophysiology of AAA, we used the angiotensin (Ang) II-induced AAA animal model and human biopsies taken at end-stage of disease to recapitulate key aspects of disease formation.Innate immune receptors such as toll-like receptors (TLRs) are known to regulate immunological processes leading to the formation and progression of vascular disease including AAA. In paper I, we aimed to investigate the role of TLR signaling under the control of the TRIF adaptor protein in the formation of AAA. Human, aneurysmal aortas displayed increased expression of TLR3 and TLR4 in surface of macrophages and T lymphocytes. AngII-induced aneurysm formation was attenuated in mice lacking the Trif gene (ApoE-/-Triʃ-/-), and these knockout mice presented with a more intact medial layer together with a reduced inflammatory response by macrophages and T lymphocytes and reduced levels of pro-inflammatory cytokines, chemokines, and proteases. Our results suggest an involvement of TRIF in the pathophysiology of AAA.Current management of AAA fully depends on imaging and surgical techniques, and drug-based therapies are still mostly ineffective. In paper II, we aimed to investigate the potential protective role of the tyrosine kinase inhibitor imatinib on the molecular mechanism involved in AAA formation. In AngII-infused ApoE-/-mice, 10 mg/kg imatinib per day affected several key features important in aneurysmal formation, including preservation of the medial layer of the VSMCs, reduced infiltrations of CD3ε-positive T lymphocytes, and reduced gene expression of mast cell chymase, resulting in decreased aortic diameter and vessel wall thickness. These results highlight the importance of the tyrosine kinase inhibitor imatinib as a potential drug in the treatment of pathological vascular inflammation and remodeling in conditions such as AAA.In paper III, we aimed to investigate the role of adiponectin in experimentally induced AAA formation in mice. In mice with elevated adiponectin levels, AAA development was inhibited, and this was associated with reduced inflammatory cell infiltration, reduced medial degeneration of VSMCs and of elastin in the aortic vessel wall together with an improved systemic cytokine profile and the attenuation of periaortic adipose tissue (PVAT) inflammation. These results support the protective effect of adiponectin in the remodeling occurring in the aortic wall and in the prevention of AAA.In paper IV, we performed a descriptive study investigating the composition of PVAT adjacent to the aneurysmal aorta. We used immunohistochemistry to identify neutrophils, macrophages, mast cells, and T lymphocytes surrounding necrotic adipocytes in PVAT together with increased gene expression of IL-6 and cathepsin K and S. We also determined the concentrations of pro-inflammatory ceramides in PVAT and found an association to T lymphocytes. These results suggest that inflamed adipose tissue might be a source of proinflammatory cells and mediators that contribute to aortic wall degeneration.
|
|
| 5. |
- Balboa Ramilo, Amanda
(författare)
-
Exploring Preclinical Targets in Abdominal Aortic Aneurysm
- 2024
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Abdominal Aortic Aneurysm (AAA) is a vascular disease characterised by the progressive and permanent dilation of the aorta, culminating in rupture and death, if not intervened. It affects 5% of men over the age of 65 years with a history of smoking. No pharmacological options are available to treat this disease. This thesis aims to investigate the role of glucose metabolism and mitochondrial function (Studies I-III) and microRNAs (Study IV) in experimental AAA and evaluate their potential as treatment targets.In Study I, angiotensin II (angII)-infused Apolipoprotein E (ApoE) deficient mice received intraperitoneal injections of the glycolysis inhibitor PFK15, for three weeks, starting one week after disease induction. Treatment with PFK15 reduced aneurysm formation compared with the control group and prevented the decrease in α-smooth cell actin/vimentin gene expression ratio caused by angII. Glycolysis inhibition with PFK15 prevents AAA growth by favouring the maintenance of a contractile phenotype of vascular smooth muscle cells.In Study II, angII-infused ApoE deficient mice received daily subcutaneous injections of the glucagon-like peptide 1 receptor analogue semaglutide, for four weeks, starting simultaneously with disease induction. Treatment with semaglutide prevented death by aortic rupture in the first seven days of disease development and the loss of collagen in the aortic wall. Semaglutide thereby prevents aortic dissection and rupture likely by promoting the maintenance of collagen in the aortic wall. In Study III, mice received angII or saline infusion for four weeks. Mitochondrial function was evaluated ex vivo in whole aortic tissue, by high-resolution respirometry. Aortas of angII-infused mice had a reduced capacity to increase oxygen consumption, in response to ADP and succinate, compared to control. These results demonstrate that it is possible to measure mitochondrial function in whole aneurysmal tissue ex vivo, and, importantly, that mitochondrial function is impaired in AAA. In Study IV, angII-infused ApoE deficient mice received four intraperitoneal injections of miR-10b, starting three days before disease induction and continuing for four weeks. Treatment with miR-10b promoted AAA development, growth and rupture, associated with an increased elastin degradation. miR-10b has an active role in promoting experimental AAA progression by boosting aortic wall degradation. In conclusion, glucose metabolism, mitochondrial function and microRNA are important pathways in the pathophysiology of AAA and promising targets for pharmacological modulation.
|
|
| 6. |
- Shamoun, Levar, 1979-
(författare)
-
Investigation of immune cell-derived factors as potential biomarkers in patients with colorectal cancer
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer related death. It is a heterogeneous disease involving multiple molecular pathways that result in differing phenotypes. Individual variability in CRC susceptibility is influenced by genetic variation, such as single nucleotide polymorphisms (SNPs). Changes in genetics and epigenetics can disrupt intact signalling pathways involved in metabolism, proliferation, differentiation, and apoptosis. Inflammatory factors such as cytokines and chemokines, as well as their receptors, play important roles in immune regulation.In Papers I, II and III, selected SNPs in the genes of interleukin (IL)-4, IL-13, IL-2 or chemokine C-C motif ligand (CCL) 4 in patients with CRC were investigated to determine their prognostic significance by identifying associations with various clinicopathological parameters and long-term survival. The investigated IL-13 and IL-4 SNPs were found to be risk factors for CRC and could be useful potential prognostic markers in CRC patient follow-up and clinical management. The investigated IL-2 SNPs were significantly associated with an increased risk of CRC and worse cancer-specific survival in patients with stage II or stage III CRC.In Paper III, levels of CCL4 protein were measured in CRC patients to investigate their prognostic significance for CRC. The data showed that CRC tissue had a higher protein expression than normal paired tissue, and plasma CCL4 levels were higher in patients than in controls, being positively correlated with CRC tissue levels. Further, higher levels of tissue CCL4 protein were linked to a lower disease stage and a better prognosis.Paper IV was an investigation of the expression of zinc finger MYND-type containing 15 (zmynd15) and its roles in CRC. In CRC tissue, protein expression was found primarily in cluster of differentiation (CD) 68 positive cells. Zmynd15 messenger ribonucleic acid expression was lower in CRC tissue than in non-cancerous tissue. When zmynd15 was silenced in CRC cell lines, it caused alteration in genes known to be important in CRC, indicating that zmynd15-regulated genes are involved in CRC. Furthermore, tumour development in the colon was higher in zmynd15 knockout mice than in wild-type mice.In conclusion, the work presented in this thesis contributes to an understanding of the association of inflammatory markers in CRC with risk and survival, and their potential use as tools for monitoring CRC patients. In addition, it showed that zmynd15, a transcriptional suppressor, plays an important role in the development of CRC.
|
|
| 7. |
- Alehagen, Urban, 1951-, et al.
(författare)
-
Genetic variance and plasma concentration of CD93 is associated with cardiovascular mortality : Results from a 6.7-year follow-up of a healthy community-living elderly population
- 2020
-
Ingår i: Molecular Medicine Reports. - : Spandidos Publications. - 1791-2997 .- 1791-3004. ; 22:6, s. 4629-4636
-
Tidskriftsartikel (refereegranskat)abstract
- Inflammation is one of the fundamental processes in numerous diseases. Cluster of differentiation (CD) 93, a glycoprotein, has been reported to be associated with a number of these diseases. There are reports indicating that a high plasma level of CD93 is associated with adverse events in ischaemic heart disease. Additionally, there are reports indicating different cardiovascular risks between different single nucleotide polymorphisms (SNPs) of CD93. Therefore, the present study aimed to determine whether the plasma concentration of CD93 and polymorphism of rs2749812 in CD93 were associated with clinical conditions and mortality in an elderly population. In 470 healthy elderly community-living individuals a novel clinical examination involving echocardiography and blood sampling was performed. The population was followed for 6.7 years. Plasma levels of CD93 and SNP analyses of rs2749812 of CD93 using PCR methodology were used. During the follow-up period, 106 (22.6%) all-cause and 61 (13.0%) cardiovascular deaths were registered. Those with the highest plasma concentration had markedly higher all-cause mortality. Evaluating the A/A, A/G and G/G genotypes, the G/G group exhibited significantly higher cardiovascular mortality (P=0.026), and an almost two-fold increased risk in a multivariate Cox regression model compared with the A/G genotype. Evaluation of subgroups with respect to sex, diabetes and hypertension revealed markedly increased cardiovascular risk in the G/G genotype in all subgroups. All results persisted in the multiple models used. In the present study, the glycoprotein CD93 was demonstrated to have prognostic cardiovascular information, with increased risk for those with a high plasma concentration. Furthermore, the G/G genotype of rs2749812 of CD93 has a significantly higher cardiovascular risk, as demonstrated here, and could therefore be regarded as a possible cardiovascular risk biomarker that might in the future be used to offer optimised cardiovascular patient handling. However, this was a small study, and more research is required.
|
|
| 8. |
- Alehagen, Urban, et al.
(författare)
-
Increased cardiovascular mortality in females with the a/a genotype of the SNPs rs1478604 and rs2228262 of thrombospondin-1
- 2020
-
Ingår i: BMC Medical Genetics. - : Springer Science and Business Media LLC. - 1471-2350. ; 21:1
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundCardiovascular diseases are still the major cause of death in the Western world, with different outcomes between the two genders. Efforts to identify those at risk are therefore given priority in the handling of health resources. Thrombospondins (TSP) are extracellular matrix proteins associated with cardiovascular diseases. The aim of this study was to investigate variations in single nucleotide polymorphisms (SNPs) of TSP-1 and plasma expression, and associations with mortality from a gender perspective.MethodsA population of 470 community-living persons were invited to participate. The participants were followed for 7.9 years and underwent a clinical examination and blood sampling. SNP analyses of TSP-1 rs1478604 and rs2228262 using allelic discrimination and plasma measurement of TSP-1 using ELISA were performed,ResultsDuring the follow-up period, 135 (28.7%) all-cause and 83 (17.7%) cardiovascular deaths were registered.In the female population, the A/A genotype of rs2228262 and the T/T genotype of rs1478604 exhibited significantly more cardiovascular deaths compared with the A/G and G/G, or the T/C and C/C genotypes amalgamated (rs2228262: 13.7% vs 2.0%; Χ2:5.29; P = 0.02; rs1478604:17.7% vs 4.7%; Χ2:9.50; P = 0.002). Applied in a risk evaluation, the A/A, or T/T genotypes exhibited an increased risk of cardiovascular mortality (rs2228262: HR: 7.1; 95%CI 1.11–45.8; P = 0.04; rs1478604: HR: 3.18; 95%CI 1.35–7.50; p = 0.008). No differences among the three genotypes could be seen in the male group.ConclusionIn this study the female group having the A/A genotype of rs2228262, or the T/T genotype of rs1478604 of TSP-1 exhibited higher cardiovascular mortality after a follow-up of almost 8 years. No corresponding genotype differences could be found in the male group. Genotype evaluations should be considered as one of the options to identify individuals at risk. However, this study should be regarded as hypothesis-generating, and more research in the field is needed.
|
|
| 9. |
- Alehagen, Urban, 1951-, et al.
(författare)
-
Increased mortality in the A/A genotype of the SNP rs28372698 of interleukin 32
- 2021
-
Ingår i: Experimental and Therapeutic Medicine. - : SPANDIDOS PUBL LTD. - 1792-0981 .- 1792-1015. ; 21:2
-
Tidskriftsartikel (refereegranskat)abstract
- One of the major causes of mortality in the western hemisphere is cardiovascular disease. Therefore, a variety of markers to identify those at risk are required. Interleukin-32 (IL-32) is a cytokine that is associated with inflammation. The aim of the current study was to investigate variations in single nucleotide polymorphisms (SNPs) of IL-32 and plasma expression, and their associations with mortality. A population of 486 elderly community-living persons were evaluated. The participants were followed for 7.1 years and underwent a clinical examination and blood sampling. SNP analyses of IL-32 rs28372698 using allelic discrimination and plasma measurement of IL-32, using ELISA, were performed. During the follow-up period, 140 (28.8%) all-cause and 87 (17.9%) cardiovascular deaths were registered. No significant difference between mortality and plasma concentration of IL-32 was observed. The A/A genotype group exhibited significantly higher all-cause mortality (P=0.036), and an almost two-fold increased risk in a multivariate Cox regression model for all-cause and cardiovascular mortality. A highly significant difference in all-cause and cardiovascular mortality between the A/A and the T/T groups was demonstrated (P=0.015 resp. P=0.014). In the present study, the cytokine IL-32 was demonstrated to have prognostic information, with an increased risk of all-cause and cardiovascular mortality for those with the A/A genotype rs28372698 of IL-32. The A/A genotype could therefore be regarded as a possible biomarker for mortality risk that may be used to offer optimized cardiovascular patient handling in the future. However, the present study sample was small, and the results should be regarded as hypothesis-generating.
|
|
| 10. |
|
|
