| 1. |
- Folkesson, Mattias, 1972-
(författare)
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Heat shock proteins in exercised human skeletal muscle
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Exercise is considered as an important stressor accompanied by concerted molecular and cellular changes leading to adaptations at the level of skeletal muscle size and function. An important protein family produced by cells in response to stressful conditions is the heat shock proteins (HSPs). It is suggested that the different HSPs play specific roles in acute and longterm responses to exercise-induced stress. The overall aim of this thesis was to explore the expression of four different HSPs (αB-crystallin, HSP27, HSP60 and HSP70) in human skeletal muscle exposed to exercise, with a special emphasis on the role played by HSP27 in the hypertrophy of human skeletal muscle.One of the major findings was the fibre type-specific expression of HSPs in resting human skeletal muscle, including the preferential expression of HSP27 in fast type II muscle fibres. Another finding was the occurrence of training background-related differences in the expression of HSPs. Also, a cytoplasmic relocation of HSP27, occurring specifically in type II muscle fibres, was shown in response to a single bout of resistance exercise. Interestingly, there were no corresponding changes in response to an endurance exercise bout, suggesting that HSP27 may be specifically involved in the adaptations to resistance exercise. In order to test this hypothesis, an in-vitro exercise model based on the electrical pulse stimulation (EPS) of muscle cells was developed. The EPS protocol, including an 8 h restitution period, induced a significant hypertrophy of muscle cells together with molecular changes similar to those previously described in response to exercise in humans. The role of HSP27 in the hypertrophy of human muscle cells was examined through the downregulation of HSP27. Based on data from morphological and microarray analyses, findings indicate that HSP27 is not mandatory for the hypertrophy of human muscle cells. Overall, the present thesis clarified the expression of different HSPs in human skeletal muscle and provided an in-vitro-based approach for the elucidation of the exact role played by HSPs in the adaptations of human skeletal muscle to exercise.
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| 2. |
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| 3. |
- Andersson, Erik, 1988-, et al.
(författare)
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Subphenotypes of inflammatory bowel disease are characterized by specific serum protein profiles
- 2017
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 12:10
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Genetic and immunological data indicate that inflammatory bowel disease (IBD) are characterized by specific inflammatory protein profiles. However, the serum proteome of IBD is still to be defined. We aimed to characterize the inflammatory serum protein profiles of Crohn's disease (CD) and ulcerative colitis (UC), using the novel proximity extension assay.Methods: A panel of 91 inflammatory proteins were quantified in a discovery cohort of CD (n = 54), UC patients (n = 54), and healthy controls (HCs; n = 54). We performed univariate analyses by t-test, with false discovery rate correction. A sparse partial least-squares (sPLS) approach was used to identify additional discriminative proteins. The results were validated in a replication cohort.Results: By univariate analysis, 17 proteins were identified with significantly different abundances in CD and HCs, and 12 when comparing UC and HCs. Additionally, 64 and 45 discriminant candidate proteins, respectively, were identified with the multivariate approach. Correspondingly, significant cross-validation error rates of 0.12 and 0.19 were observed in the discovery cohort. Only FGF-19 was identified from univariate comparisons of CD and UC, but 37 additional discriminant candidates were identified using the multivariate approach. The observed cross-validation error rate for CD vs. UC remained significant when restricting the analyses to patients in clinical remission. Using univariate comparisons, 16 of 17 CD-associated proteins and 8 of 12 UC-associated proteins were validated in the replication cohort. The area under the curve for CD and UC was 0.96 and 0.92, respectively, when the sPLS model from the discovery cohort was applied to the replication cohort.Conclusions: By using the novel PEA method and a panel of inflammatory proteins, we identified proteins with significantly different quantities in CD patients and UC patients compared to HCs. Our data highlight the potential of the serum IBD proteome as a source for identification of future diagnostic biomarkers.
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| 4. |
- Bang, Charlotte Sahlberg, 1967-, et al.
(författare)
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Global gene expression profiling and antibiotic susceptibility after repeated exposure to the carbon monoxide-releasing molecule-2 (CORM-2) in multidrug-resistant ESBL-producing uropathogenic Escherichia coli
- 2017
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- Treatment of urinary tract infections is today a challenge due to the increasing prevalence of multidrug-resistant ESBL-producing uropathogenic Escherichia coli (UPEC). There is an urgent need for new treatment strategies for multidrug-resistant UPEC and preferably with targets that have low potential for development of resistance. Carbon monoxide-releasing molecules (CORMs) are novel and potent antibacterial agents. The present study examines the transcriptomic targets of CORM-2 in a multidrug-resistant ESBL-producing UPEC isolate in response to a single exposure to CORM-2 and after repeated exposure to CORM-2. The bacterial viability and minimal inhibitory concentration (MIC) were also examined after repeated exposure to CORM-2. Microarray analysis revealed that a wide range of processes were affected by CORM-2, including a general trend of down-regulation in energy metabolism and biosynthesis pathways and up-regulation of the SOS response and DNA repair. Several genes involved in virulence (ibpB), antibiotic resistance (marAB, mdtABC) and biofilm formation (bhsA, yfgF) were up-regulated, while some genes involved in virulence (kpsC, fepCEG, entABE), antibiotic resistance (evgA) and biofilm formation (artIP) were down-regulated. Repeated exposure to CORM-2 did not alter the gene expression patterns, the growth inhibitory response to CORM-2 or the MIC values for CORM-2, cefotaxime, ciprofloxacin and trimethoprim. This study identifies several enriched gene ontologies, modified pathways and single genes that are targeted by CORM-2 in a multidrug-resistant UPEC isolate. Repeated exposure to CORM-2 did not change the gene expression patterns or fold changes and the susceptibility to CORM-2 remained after repeated exposure.
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| 5. |
- Bergemalm, Daniel, 1977-, et al.
(författare)
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Elevated fecal peptidase D at onset of colitis in Galphai2(-/-) mice, a mouse model of IBD
- 2017
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 12:3
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Tidskriftsartikel (refereegranskat)abstract
- Background The identification of novel fecal biomarkers in inflammatory bowel disease (IBD) is hampered by the complexity of the human fecal proteome. On the other hand, in experimental mouse models there is probably less variation. We investigated the fecal protein content in mice to identify possible biomarkers and pathogenic mechanisms. Fecal samples were collected at onset of inflammation in Galphai2(-/-) mice, a well-described spontaneous model of chronic colitis, and from healthy littermates. The fecal proteome was analyzed by two-dimensional electrophoresis and quantitative mass spectrometry and results were then validated in a new cohort of mice. As a potential top marker of disease, peptidase D was found at a higher ratio in Galphai24mouse feces relative to controls (fold change 27; p = 0.019). Other proteins found to be enriched in Gai2(-/-) mice were mainly pancreatic proteases, and proteins from plasma and blood cells. A tendency of increased calprotectin, subunit S100-A8, was also observed (fold change 21; p = 0.058). Proteases are potential activators of inflammation in the gastrointestinal tract through their interaction with the proteinase-activated receptor 2 (PAR2). Accordingly, the level of PAR2 was found to be elevated in both the colon and the pancreas of Galphai24- mice at different stages of disease. These findings identify peptidase D, an ubiquitously expressed intracellular peptidase, as a potential novel marker of colitis. The elevated levels of fecal proteases may be involved in the pathogenesis of colitis and contribute to the clinical phenotype, possibly by activation of intestinal PAR2.
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| 6. |
- Demirel, Isak, 1987-, et al.
(författare)
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Activation of the NLRP3 Inflammasome Pathway by Uropathogenic Escherichia coli Is Virulence Factor-Dependent and Influences Colonization of Bladder Epithelial Cells
- 2018
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Ingår i: Frontiers in Cellular and Infection Microbiology. - : Frontiers Media S.A.. - 2235-2988. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- The NLRP3 inflammasome and IL-1 beta release have recently been suggested to be important for the progression of urinary tract infection (UTI). However, much is still unknown regarding the interaction of UPEC and the NLRP3 inflammasome. The purpose of this study was to elucidate what virulence factors uropathogenic Escherichia coil (UPEC) use to modulate NLRP3 inflammasome activation and subsequent IL-1 beta release and the role of NLRP3 for UPEC colonization of bladder epithelial cells. The bladder epithelial cell line 5637, CRISPR/Cas9 generated NLRP3, caspase-1 and mesotrypsin deficient cell lines and transformed primary bladder epithelial cells (HBLAK) were stimulated with UPEC isolates and the non-pathogenic MG1655 strain. We found that the UPEC strain CFT073, but not MG1655, induced an increased caspase-1 activity and IL-1 beta release from bladder epithelial cells. The increase was shown to be mediated by et-hemolysin activation of the NLRP3 inflammasome in an NE-kappa B-independent manner. The effect of-hemolysin on IL-1 beta release was biphasic, initially suppressive, later inductive. Furthermore, the phase-locked type-1-fimbrial ON variant of CFT073 inhibited caspase-1 activation and IL-1 beta release. In addition, the ability of CFT073 to adhere to and invade NLRP3 deficient cells was significantly reduced compare to wild-type cells. The reduced colonization of NLRP3-deficient cells was type-1 fimbriae dependent. In conclusion, we found that the NLRP3 inflammasome was important for type-1 fimbriae-dependent colonization of bladder epithelial cells and that both type-1 fimbriae and alpha-hemolysin can modulate the activity of the NLRP3 inflammasome.
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| 7. |
- Demirel, Isak, 1987-, et al.
(författare)
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Ceftibuten-induced filamentation of extended spectrum beta lactamase (ESBL)-producing uropathogenic Escherichia coli alters host cell responses during an in vitro infection
- 2015
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Ingår i: Microbial Pathogenesis. - : Elsevier. - 0882-4010 .- 1096-1208. ; 78, s. 52-62
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Tidskriftsartikel (refereegranskat)abstract
- Inadequate and delayed antibiotic treatment of extended spectrum beta-lactamase (ESBL)-producing isolates have been associated with increased mortality of affected patients. The purpose of this study was to compare the host response of human renal epithelial cells and polymorphonuclear leucocyte (PMN) cells when infected by ESBL-producing uropathogenic Escherichia coli (UPEC) isolates in the presence or absence of ineffective antibiotics.The renal epithelial cell line A498 and PMN cells were stimulated with ESBL-producing UPEC isolates in the presence or absence of three different antibiotics (trimetoprim, ceftibuten and ciprofloxacin). Host cell responses were evaluated as release of cytokines (IL-6, IL-8), reactive oxygen species (ROS), ATP and endotoxins. Bacterial morphology and PMN phagocytosis were evaluated by microscopy.In the presence of ceftibuten, 2 out of 3 examined ESBL-isolates changed their morphology into a filamentous form. The presence of ceftibuten enhanced IL-6, IL-8 and ROS-production from host cells, but only from cells stimulated by the filamentous isolates. The bacterial supernatant and not the filamentous bacteria per se was responsible for the increased release of IL-6, IL-8 and ROS. Increased endotoxin and ATP levels were found in the bacterial supernatants from filamentous isolates. Apyrase decreased IL-6 secretion from A498 cells and polymyxin B abolished the increased ROS-production from PMN cells. PMN were able to inhibit the bacterial growth of some ESBL-isolates in the presence of ceftibuten.In conclusion, antibiotic-induced filamentation of ESBL-producing UPEC isolates and the associated release of ATP and endotoxins can alter the host cell response in the urinary tract.
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| 8. |
- Demirel, Isak, 1987-, et al.
(författare)
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Transcriptional Alterations of Virulence-Associated Genes in Extended Spectrum Beta-Lactamase (ESBL)-Producing Uropathogenic Escherichia coli during Morphologic Transitions Induced by Ineffective Antibiotics
- 2017
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Ingår i: Frontiers in Microbiology. - : Frontiers Media S.A.. - 1664-302X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- It is known that an ineffective antibiotic treatment can induce morphological shifts in uropathogenic Escherichia coli (UPEC) but the virulence properties during these shifts remain to be studied. The present study examines changes in global gene expression patterns and in virulence factor-associated genes in an extended spectrum beta-lactamase (ESBL)-producing UPEC (ESBL019) during the morphologic transitions induced by an ineffective antibiotic and in the presence of human primary bladder epithelial cells. Microarray results showed that the different morphological states of ESBL019 had significant transcriptional alterations of a large number of genes (Transition; 7%, Filamentation; 32%, and Reverted 19% of the entities on the array). All three morphological states of ESBL019 were associated with a decreased energy metabolism, altered iron acquisition systems and altered adhesion expression. In addition, genes associated with LPS synthesis and bacterial motility was also altered in all the morphological states. Furthermore, the transition state induced a significantly higher release of TNF-alpha from bladder epithelial cells compared to all other morphologies, while the reverted state was unable to induce INF-alpha release. Our findings show that the morphological shifts induced by ineffective antibiotics are associated with significant transcriptional virulence alterations in ESBL-producing UPEC, which may affect survival and persistence in the urinary tract.
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| 9. |
- Sahlberg Bang, Charlotte, 1967-, et al.
(författare)
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Carbon monoxide releasing molecule-2 (CORM-2) inhibits growth of multidrug-resistant uropathogenic Escherichia coli in biofilm and following host cell colonization
- 2016
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Ingår i: BMC Microbiology. - : BioMed Central. - 1471-2180. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Increased resistance to antimicrobial agents is a characteristic of many bacteria growing in biofilms on for example indwelling urinary catheters or in intracellular bacterial reservoirs. Biofilm-related infections caused by multidrug-resistant bacteria, such as extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, are a major challenge. The aim of this study was to investigate if a carbon monoxide-releasing molecule (CORM-2) has antibacterial effects against ESBL-producing uropathogenic E. coli (UPEC) in the biofilm mode of growth and following colonization of host bladder epithelial cells.ResultsThe effect of CORM-2 was examined on bacteria grown within an established biofilm (biofilm formed for 24 h on plastic surface) by a live/dead viability staining assay. CORM-2 (500 μM) exposure for 24 h killed approximately 60 % of the ESBL-producing UPEC isolate. A non-ESBL-producing UPEC isolate and the E. coli K-12 strain TG1 were also sensitive to CORM-2 exposure when grown in biofilms. The antibacterial effect of CORM-2 on planktonic bacteria was reduced and delayed in the stationary growth phase compared to the exponential growth phase. In human bladder epithelial cell colonization experiments, CORM-2 exposure for 4 h significantly reduced the bacterial counts of an ESBL-producing UPEC isolate.ConclusionThis study shows that CORM-2 has antibacterial properties against multidrug-resistant UPEC under biofilm-like conditions and following host cell colonization, which motivate further studies of its therapeutic potential.
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