| 1. |
- Andersson, Karin, 1972, et al.
(författare)
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Pathogenic Transdifferentiation of Th17 Cells Contribute to Perpetuation of Rheumatoid Arthritis during Anti-TNF Treatment.
- 2015
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Ingår i: Molecular medicine (Cambridge, Mass.). - : Springer Science and Business Media LLC. - 1528-3658 .- 1076-1551. ; 21, s. 536-43
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Tidskriftsartikel (refereegranskat)abstract
- T-helper cells producing interleukin (IL)-17A and IL-17F cytokines (Th17 cells) are considered the source of autoimmunity in rheumatoid arthritis (RA). In this study, we characterized specific pathogenic features of Th17 cells in RA. By using nano-string technology, we analyzed transcription of 419 genes in the peripheral blood CCR6(+)CXCR3(-) CD4(+) cells of 14 RA patients and 6 healthy controls and identified 109 genes discriminating Th17 cells of RA patients from the controls. Th17 cells of RA patients had an aggressive pathogenic profile and in addition to signature cytokines IL-17, IL-23 and IL-21, and transcriptional regulators RAR-related orphan receptor gamma of T cells (RORγt) and Janus kinase 2 (JAK2), they produced high levels of IL-23R, C-C chemokine ligand type 20 (CCL20), granulocyte-monocyte colony-stimulating factor (GM-CSF ) and transcription factor Tbet required for synovial homing. We showed that Th17 cells are enriched with Helios-producing Foxp3- and IL2RA-deficient cells, indicating altered regulatory profile. The follicular T-helper (Tfh) cells presented a functional profile of adaptor molecules, transcriptional regulator Bcl-6 and B-cell activating cytokines IL-21, IL-31 and leukemia inhibitory factor (LIF ). We observed that anti-tumor necrosis factor (TNF) treatment had a limited effect on the transcription signature of Th17 cells. Patients in remission retained the machinery of receptors (IL-23R and IL-1R1), proinflammatory cytokines (IL-17F, IL-23, IL-21 and TNF ) and adaptor molecules (C-X-C chemokine receptor 5 [CXCR5] and cytotoxic T-lymphocyte-associated protein 4 [CTLA-4]), essential for efficient transdifferentiation and accumulation of Th17 cells. This study convincingly shows that the peripheral blood CCR6(+)CXCR3(-) CD4(+) cells of RA patients harbor pathogenic subsets of Th17 and Tfh cells, which may transdifferentiate from Tregs and contribute to perpetuation of the disease.
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| 2. |
- Brisslert, Mikael, 1974, et al.
(författare)
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Epstein-Barr virus infection transforms CD25(+) B cells into antibody-secreting cells in rheumatoid arthritis patients
- 2013
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Ingår i: Immunology. - : Wiley. - 0019-2805. ; 140:4, s. 421-429
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Tidskriftsartikel (refereegranskat)abstract
- Epstein-Barr virus (EBV) infection may initiate production of autoantibodies and development of cancer and autoimmune diseases. Here we outline phenotypic and functional changes in B cells of patients with rheumatoid arthritis (RA) related to EBV infection. The B-cell phenotype was analysed in blood and bone marrow (BM) of RA patients who had EBV transcripts in BM (EBV+, n=13) and in EBV- (n=22) patients with RA. The functional effect of EBV was studied in the sorted CD25(+) and CD25(-) peripheral B cells of RA patients (n=18) and healthy controls (n=9). Rituximab treatment results in enrichment of CD25(+) B cells in peripheral blood (PB) of EBV+ RA patients. The CD25(+) B-cell subset displayed a more mature phenotype accumulating IgG-expressing cells. It was also enriched with CD27(+) and CD95(+) cells in PB and BM. EBV stimulation of the sorted CD25(+) B cells in vitro induced a polyclonal IgG and IgM secretion in RA patients, while CD25(+) B cells of healthy subjects did not respond to EBV stimulation. CD25(+) B cells were enriched in PB and synovial fluid of RA patients. EBV infection affects the B-cell phenotype in RA patients by increasing the CD25(+) subset and by inducing their immunoglobulin production. These findings clearly link CD25(+) B cells to the EBV-dependent sequence of reactions in the pathogenesis of RA.
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| 3. |
- Chandrasekaran, Venkatagaran, et al.
(författare)
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Cohesin-Mediated Chromatin Interactions and Autoimmunity
- 2022
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Proper physiological functioning of any cell type requires ordered chromatin organization. In this context, cohesin complex performs important functions preventing premature separation of sister chromatids after DNA replication. In partnership with CCCTC-binding factor, it ensures insulator activity to organize enhancers and promoters within regulatory chromatin. Homozygous mutations and dysfunction of individual cohesin proteins are embryonically lethal in humans and mice, which limits in vivo research work to embryonic stem cells and progenitors. Conditional alleles of cohesin complex proteins have been generated to investigate their functional roles in greater detail at later developmental stages. Thus, genome regulation enabled by action of cohesin proteins is potentially crucial in lineage cell development, including immune homeostasis. In this review, we provide current knowledge on the role of cohesin complex in leukocyte maturation and adaptive immunity. Conditional knockout and shRNA-mediated inhibition of individual cohesin proteins in mice demonstrated their importance in haematopoiesis, adipogenesis and inflammation. Notably, these effects occur rather through changes in transcriptional gene regulation than through expected cell cycle defects. This positions cohesin at the crossroad of immune pathways including NF-kB, IL-6, and IFN gamma signaling. Cohesin proteins emerged as vital regulators at early developmental stages of thymocytes and B cells and after antigen challenge. Human genome-wide association studies are remarkably concordant with these findings and present associations between cohesin and rheumatoid arthritis, multiple sclerosis and HLA-B27 related chronic inflammatory conditions. Furthermore, bioinformatic prediction based on protein-protein interactions reveal a tight connection between the cohesin complex and immune relevant processes supporting the notion that cohesin will unearth new clues in regulation of autoimmunity.
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| 4. |
- Erlandsson, Malin, 1972, et al.
(författare)
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Survivin promotes a glycolytic switch in CD4+ T cells by suppressing the transcription of PFKFB3 in rheumatoid arthritis.
- 2022
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Ingår i: iScience. - : Elsevier BV. - 2589-0042. ; 25:12
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we explore the role of nuclear survivin in maintaining the effector phenotype of IFNγ-producing Tcells acting through the transcriptional control of glucose utilization. High expression of survivin in CD4+T cells was associated with IFNγ-dependent phenotype and anaerobic glycolysis. Transcriptome of CD4+ cells and sequencing of survivin-bound chromatin showed that nuclear survivin had a genome-wide and motif-specific binding to regulatory regions of the genes controlling cell metabolism. Survivin coprecipitates with transcription factors IRF1 and SMAD3, which repressed the transcription of the metabolic check-point enzyme phosphofructokinase 2 gene PFKFB3 and promoted anaerobic glycolysis. Combining transcriptome analyses of CD4+ cells and functional studies in glucose metabolism, we demonstrated that the inhibition of survivin reverted PFKFB3 production, inhibited glucose uptake, and reduces interferon effects in CD4+ cells. These results present a survivin-dependent mechanism in coordinating the metabolic adaptation of CD4+T cells and propose an attractive strategy to counteract IFNγ-dependent inflammation in autoimmunity.
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| 5. |
- Fatima, Farah, et al.
(författare)
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Radiological features of experimental staphylococcal septic arthritis by micro computed tomography scan.
- 2017
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- Permanent joint dysfunction due to bone destruction occurs in up to 50% of patients with septic arthritis. Recently, imaging technologies such as micro computed tomography (μCT) scan have been widely used for preclinical models of autoimmune joint disorders. However, the radiological features of septic arthritis in mice are still largely unknown.NMRI mice were intravenously or intra-articularly inoculated with S. aureus Newman or LS-1 strain. The radiological and clinical signs of septic arthritis were followed for 10 days using μCT. We assessed the correlations between joint radiological changes and clinical signs, histological changes, and serum levels of cytokines.On days 5-7 after intravenous infection, bone destruction verified by μCT became evident in most of the infected joints. Radiological signs of bone destruction were dependent on the bacterial dose. The site most commonly affected by septic arthritis was the distal femur in knees. The bone destruction detected by μCT was positively correlated with histological changes in both local and hematogenous septic arthritis. The serum levels of IL-6 were significantly correlated with the severity of joint destruction.μCT is a sensitive method for monitoring disease progression and determining the severity of bone destruction in a mouse model of septic arthritis. IL-6 may be used as a biomarker for bone destruction in septic arthritis.
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| 6. |
- Garcia-Bonete, Maria-Jose, 1989, et al.
(författare)
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Bayesian Analysis of MicroScale Thermophoresis Data to Quantify Affinity of Protein: Protein Interactions with Human Survivin
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 7:1, s. Art. no. 16816-
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Tidskriftsartikel (refereegranskat)abstract
- A biomolecular ensemble exhibits different responses to a temperature gradient depending on its diffusion properties. MicroScale Thermophoresis technique exploits this effect and is becoming a popular technique for analyzing interactions of biomolecules in solution. When comparing affinities of related compounds, the reliability of the determined thermodynamic parameters often comes into question. The thermophoresis binding curves can be assessed by Bayesian inference, which provides a probability distribution for the dissociation constant of the interacting partners. By applying Bayesian machine learning principles, binding curves can be autonomously analyzed without manual intervention and without introducing subjective bias by outlier rejection. We demonstrate the Bayesian inference protocol on the known survivin: borealin interaction and on the putative protein-protein interactions between human survivin and two members of the human Shugoshin-like family (hSgol1 and hSgol2). These interactions were identified in a protein microarray binding assay against survivin and confirmed by MicroScale Thermophoresis.
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| 7. |
- Gravina, Giacomo, et al.
(författare)
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Survivin in autoimmune diseases.
- 2017
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Ingår i: Autoimmunity reviews. - : Elsevier BV. - 1873-0183 .- 1568-9972. ; 16:8, s. 845-855
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Forskningsöversikt (refereegranskat)abstract
- Survivin is a protein functionally important for cell division, apoptosis, and possibly, for micro-RNA biogenesis. It is an established marker of malignant cell transformation. In non-malignant conditions, the unique properties of survivin make it indispensable for homeostasis of the immune system. Indeed, it is required for the innate and adaptive immune responses, controlling differentiation and maintenance of CD4(+) and CD8(+) memory T-cells, and in B cell maturation. Recently, survivin has emerged as an important player in the pathogenesis of autoimmune diseases. Under the conditions of unreserved inflammation, survivin enhances antigen presentation, maintains persistence of autoreactive cells, and supports production of autoantibodies. In this context, survivin takes its place as a diagnostic and prognostic marker in rheumatoid arthritis, psoriasis, systemic sclerosis and pulmonary arterial hypertension, neuropathology and multiple sclerosis, inflammatory bowel diseases and oral lichen planus. In this review, we summarise the knowledge about non-malignant properties of survivin and focus on its engagement in cellular and molecular pathology of autoimmune diseases. The review highlights utility of survivin measures for clinical applications. It provides rational for the survivin inhibiting strategies and presents results of recent reports on survivin inhibition in modern therapies of cancers and autoimmune diseases.
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| 8. |
- Jensen, Maja, 1978, et al.
(författare)
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Survivin prevents the polycomb repressor complex 2 from methylating histone 3 lysine 27
- 2023
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Ingår i: Iscience. ; 26:7
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the role of survivin in epigenetic control of gene transcription through interaction with the polycomb repressive complex 2 (PRC2). PRC2 is responsible for silencing gene expression by trimethylating lysine 27 on histone 3. We observed differential expression of PRC2 subunits in CD4(+) T cells with varying levels of survivin expression, and ChIP-seq results indicated that survivin colocalizes with PRC2 along DNA. Inhibition of survivin resulted in a significant increase in H3K27 trimethylation, implying that survivin prevents PRC2 from functioning. Peptide microarray showed that survivin interacts with peptides from PRC2 subunits, and machine learning revealed that amino acid composition contains relevant information for predicting survivin interaction. NMR and BLI experiments supported the interaction of survivin with PRC2 subunit EZH2. Finally, protein-protein docking revealed that the survivin-EZH2 interaction interface overlaps with catalytic residues of EZH2, potentially inhibiting its H3K27 methylation activity. These findings suggest that survivin inhibits PRC2 function.
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| 9. |
- Larasati Anindya, Atsarina, et al.
(författare)
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Bayesian progress curve analysis of MicroScale thermophoresis data
- 2022
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Ingår i: Digital Discovery. - : Royal Society of Chemistry (RSC). - 2635-098X. ; 1:3, s. 325-332
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Tidskriftsartikel (refereegranskat)abstract
- MicroScale Thermophoresis (MST) follows the movement of fluorescent-labelled biomolecules with different sizes along a temperature gradient. The presence of a “contrary trend” pattern, that is, the trend of fluorescence change reversing at higher titrant concentrations, is a well-known problem with uncertain cause. Conventionally, binding curves and kinetic parameters are derived from MST datasets using regression analysis on isolated time windows, while the rest of the data are ignored, and the “contrary trend” fluorescent levels are also usually removed as outliers. This biased approach can be avoided with a more continuous analysis of the entire kinetic process. The Bayesian model of MST progress curves allows the inference of parameters and modelling of the whole experiment. The removal of unusual data points is unnecessary once the anomalous kinetic process is identified. This alternative data analysis approach was applied to our MST datasets from survivin–hSgol2 interactions, and the results show that the binding curves remained sigmoid when all data were included. We were also able to infer the value and uncertainty of the dissociation constant (KD) by ascribing the anomalous data points to a new, linear kinetic component. This approach demonstrates good posterior predictions from the MST process in both short and longer experiments as well as the feasibility of KD inference from short experiments.
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| 10. |
- Oparina, Nina, et al.
(författare)
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Prognostic Significance of BIRC5/Survivin in Breast Cancer: Results from Three Independent Cohorts.
- 2021
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Ingår i: Cancers. - : MDPI AG. - 2072-6694. ; 13:9
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Tidskriftsartikel (refereegranskat)abstract
- Breast cancer (BC) histological and molecular classifications significantly improved the treatment strategy and prognosis. Inhibitor of apoptosis BIRC5/survivin is often overexpressed in cancers, however, indications of its importance in BC are inconsistent. We integrate BIRC5 protein and mRNA measures with clinical associates and long-term outcome in three independent cohorts Protein levels of BIRC5 were measured in primary lysates of 845 patients of the West Swedish BC cohort (VGR-BC) and linked to 5- and 27-years survival. The results were externally validated in transcriptomic data from METABRIC and SCAN-B cohorts. Survival analysis showed that high levels of BIRC5 were consistently associated with a poor probability of 5-year overall survival. High BIRC5 in VGR-BC contributed negatively to the disease-specific survival at 5 and 27 years. Subsets with different status by ER (estrogen receptor) expression and presence of nodal metastasis supported independent association of high BIRC5 with poor prognosis in all cohorts. In METABRIC and SCAN-B cohorts, high levels of BIRC5 mRNA were associated with the basal-like and luminal B molecular BC subtypes and with increasing histologic grade. BIRC5 is a sensitive survival marker that acts independent of ER and nodal status, and its levels need to be considered when making treatment decisions.
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| 11. |
- Rehnberg, Maria, 1984, et al.
(författare)
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Short- and long-term effects of anti-CD20 treatment on B cell ontogeny in bone marrow of patients with rheumatoid arthritis.
- 2009
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Ingår i: Arthritis research & therapy. - : Springer Science and Business Media LLC. - 1478-6362 .- 1478-6354. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: In the present study we evaluated changes in the B cell phenotype in peripheral blood and bone marrow (BM) of patients with rheumatoid arthritis (RA) following anti-CD20 treatment using rituximab. METHODS: Blood and BM samples were obtained from 37 patients with RA prior to rituximab treatment. Ten of these patients were resampled 1 month following rituximab, 14 patients after 3 months and the remaining 13 patients were included in the long-term follow up. B cell populations were characterized by CD27/IgD/CD38/CD24 expression. RESULTS: One and three months following rituximab BM retained up to 30% of B cells while circulation was totally depleted of B cells. Analysis of the remaining BM B cells showed prevalence of immature and/or transitional B cells (CD38++CD24++) and CD27+IgD- memory cells, while IgD+ cells were completely depleted. A significant reduction of CD27+ cells in BM and in circulation was observed long after rituximab treatment (mean 22 months), while levels of naive B cells in BM and in circulation were increased. The levels of rheumatoid factor decline after rituximab treatment but returned to baseline levels at the time of retreatment. CONCLUSIONS: Anti-CD20 treatment achieves a depletion of IgD+ B cells shortly after the treatment. At the long term follow up, a reduction of CD27+ B cells was observed in blood and BM. The prolonged inability to up-regulate CD27 may inhibit the renewal of memory B cells. This reduction of CD27+ B cells does not prevent autoantibody production suggesting that mechanisms regulating the formation of auto reactive clones are not disrupted by rituximab.
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| 12. |
- Rehnberg, Maria, 1984, et al.
(författare)
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Vaccination response to protein and carbohydrate antigens in patients with rheumatoid arthritis after rituximab treatment.
- 2010
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Ingår i: Arthritis research & therapy. - : Springer Science and Business Media LLC. - 1478-6362 .- 1478-6354. ; 12:3
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Rheumatoid arthritis (RA) is frequently complicated with infections. The aim of our study was to evaluate vaccination response in patients with RA after B-cell depletion by using rituximab. METHODS: Influenza (Afluria) and pneumococcal polysaccharides (Pneumo23) vaccines were given 6 months after rituximab (post-RTX group, n=11) or 6 days before rituximab treatment (pre-RTX group; n=8). RA patients never exposed to RTX composed the control group (n=10). Vaccine-specific cellular responses were evaluated on day 6 after vaccination, and vaccine-specific humoral responses, on day 21. RESULTS: On day 6 after vaccination, formation of influenza-specific B cells was lower in post-RTX group as compared with the pre-RTX group and controls (P=0.04). Polysaccharide-specific B cells were found in 27% to 50%, being equally distributed between the groups. On day 21, the impairment of humoral responses was more pronounced with respect to influenza as compared with the pneumococcal vaccine and affected both IgG and light-chain production. Total absence of influenza-specific IgG production was observed in 55% of the post-RTX group. CONCLUSIONS: RTX compromises cellular and humoral vaccine responses in RA patients. However, repeated RTX treatment or previous anti-tumor necrosis factor (anti-TNF) treatment did not accentuate these defects.
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| 13. |
- Strandberg, Louise, 1981, et al.
(författare)
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Mice chronically fed high-fat diet have increased mortality and disturbed immune response in sepsis.
- 2009
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 4:10
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Sepsis is a potentially deadly disease that often is caused by gram-positive bacteria, in particular Staphylococcus aureus (S. aureus). As there are few effective therapies for sepsis, increased basic knowledge about factors predisposing is needed. METHODOLOGY/PRINCIPAL FINDINGS: The purpose of this study was to study the effect of Western diet on mortality induced by intravenous S. aureus inoculation and the immune functions before and after bacterial inoculation. Here we show that C57Bl/6 mice on high-fat diet (HFD) for 8 weeks, like genetically obese Ob/Ob mice on low-fat diet (LFD), have increased mortality during S. aureus-induced sepsis compared with LFD-fed C57Bl/6 controls. Bacterial load in the kidneys 5-7 days after inoculation was increased 10-fold in HFD-fed compared with LFD-fed mice. At that time, HFD-fed mice had increased serum levels and fat mRNA expression of the immune suppressing cytokines interleukin-1 receptor antagonist (IL-1Ra) and IL-10 compared with LFD-fed mice. In addition, HFD-fed mice had increased serum levels of the pro-inflammatory IL-1beta. Also, HFD-fed mice with and without infection had increased levels of macrophages in fat. The proportion and function of phagocytosing granulocytes, and the production of reactive oxygen species (ROS) by peritoneal lavage cells were decreased in HFD-fed compared with LFD-fed mice. CONCLUSIONS: Our findings imply that chronic HFD disturb several innate immune functions in mice, and impairs the ability to clear S. aureus and survive sepsis.
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| 14. |
- Öhrnell Malekzadeh, Behnosh, et al.
(författare)
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Effects of implant-delivered insulin on bone formation in osteoporotic rats
- 2018
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Ingår i: Journal of Biomedical Materials Research - Part A. - : Wiley. - 1549-3296 .- 1552-4965. ; 106:9, s. 2472-80
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 Wiley Periodicals, Inc. Osteoporosis is a major cause of age-related fractures. Healing complications in osteoporotic patients are often associated with increased mortality and morbidity. Stimulation of the implant-adjacent bone could be beneficial in terms of the surgical outcome. Over the past decade, numerous investigations have implicated insulin in normal bone growth, and recent studies have described the advantages of administering insulin locally to increase bone formation. Therefore, we hypothesized that insulin-coated titanium implants would increase bone formation in osteoporotic animals. The aim of this study was to evaluate the effects of insulin delivered from an implant surface on bone-related gene expression and bone formation in osteoporotic rats. Characterizations of the surfaces of insulin-coated and control implants were performed using ellipsometry and interferometry. Forty ovariectomized and four healthy Sprague Dawley rats were used and implants were inserted in the tibias. The systemic effect of insulin was assessed by measuring the blood glucose levels and total body weight. The animals were sacrificed either 1 day or 3 weeks postimplantation. Implant-adherent cells were analyzed by quantitative real-time PCR, and the bone adjacent to the implants was examined by microcomputed tomography and histomorphometry. The insulin-coated implants had no systemic effects. The insulin-coated samples demonstrated significantly lower expression of the gene for interleukin 1β (p=0.019) at 1 day, and significantly exhibited more periosteal callus (p=0.029) at 3 weeks. Locally delivered insulin has potential for promoting bone formation and it exerts potentially anti-inflammatory effects in osteoporotic rats.
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| 15. |
- Adlesic, M., et al.
(författare)
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Histamine in rheumatoid arthritis
- 2007
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Ingår i: Scand J Immunol. - : Wiley. - 0300-9475 .- 1365-3083. ; 65:6, s. 530-7
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Tidskriftsartikel (refereegranskat)abstract
- Rheumatoid arthritis (RA) is an autoimmune disease characterized by a persistent inflammation of the synovium, leading to the erosion of articular cartilage and bone. Synovial mast cells and their effector molecule, histamine, receive increased attention as mediators of joint inflammation. The aim of our study was to analyse levels of free histamine in serum and joint fluid of RA patients and to evaluate the potential inflammatogenic properties of histamine in vivo and in vitro. Histamine levels were measured by an ELISA in synovial fluid and sera of RA patients and of healthy controls. Histamine levels were also assessed in plasma of RA patients undergoing anti-TNF-alpha treatment. In the murine part of the study, histamine was injected intra-articularly in the knee joint of mice and the joints were subsequently analysed with respect to induction of inflammation. RA patients displayed significantly lower levels of histamine in circulation (0.93 +/- 0.16 ng/ml) compared with the healthy controls (1.89 +/- 0.45 ng/ml, P < 0.001). Locally, in synovial fluid the levels of histamine were even lower (0.37 +/- 0.16 ng/ml, P < 0.0006). Long-term anti-TNF-alpha treatment significantly increased circulating levels of histamine in RA patients. Our experiments on animals show that histamine on its own neither induces inflammation in the joint cavity nor influences the course of HMGB1 and peptidoglycan-induced joint inflammation. Based on our experimental and clinical studies we suggest that histamine lacks harmful properties in RA.
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| 16. |
- Akula, Murali K, et al.
(författare)
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Protein prenylation restrains innate immunity by inhibiting Rac1 effector interactions
- 2019
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Rho family proteins are prenylated by geranylgeranyltransferase type I (GGTase-I), which normally target proteins to membranes for GTP-loading. However, conditional deletion of GGIase-I in mouse macrophages increases GTP-loading of Rho proteins, leading to enhanced inflammatory responses and severe rheumatoid arthritis. Here we show that heterozygous deletion of the Rho family gene Rac1, but not Rhoa and Cdc42, reverses inflammation and arthritis in GGTase-I-deficient mice. Non-prenylated Rac1 has a high affinity for the adaptor protein Ras GTPase-activating-like protein 1 (Iqgap1), which facilitates both GTP exchange and ubiquitination-mediated degradation of Rac1. Consistently, inactivating lagapl normalizes Rac1 GTP-loading, and reduces inflammation and arthritis in GGTase-I-deficient mice, as well as prevents statins from increasing Rac1 GTP-loading and cytokine production in macrophages. We conclude that blocking prenylation stimulates Rac1 effector interactions and unleashes proinflammatory signaling. Our results thus suggest that prenylation normally restrains innate immune responses by preventing Rac1 effector interactions.
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| 17. |
- Almehed, Katarina, 1966, et al.
(författare)
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Role of resistin as a marker of inflammation in systemic lupus erythematosus.
- 2008
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Ingår i: Arthritis research & therapy. - : Springer Science and Business Media LLC. - 1478-6362 .- 1478-6354. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Resistin is a cystein-rich secretory adipokine. It is proposed to have proinflammatory properties in humans. The aim of this study was to determine associations between serum levels of resistin and markers of inflammation and bone mineral density (BMD) in female patients with systemic lupus erythematosus (SLE). METHODS: One hundred sixty-three female patients with SLE (20 to 82 years old) were examined in a cross-sectional study. Venous blood samples were analyzed for resistin, erythrocyte sedimentation rate (ESR), C-reactive protein, creatinine, fasting lipids, complements, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6, sIL-6R (soluble IL-6 receptor), ICTP (C-terminal telopeptide of type I collagen), and PINP (N-terminal propeptide of type I procollagen). Simple and multiple regression analyses as well as logistic regression analyses were performed. Resistin in serum was compared with 42 healthy female controls with respect to age. RESULTS: Serum resistin levels in controls were similar to those of patients with SLE. Markers of inflammation and current dose of glucocorticosteroids correlated positively to resistin in serum. Markers of renal function, number of prevalent vertebral fractures, and BMD were also significantly associated with resistin. In a multiple regression model, ESR, creatinine, C3, current glucocorticosteroid dose, high-density lipoprotein, and BMD radius remained significantly associated with resistin. In logistic regression analyses with resistin as the independent variable, a significant association was found with ESR (normal or elevated) but not with S-creatinine or z score for hip and radius total. CONCLUSION: Although resistin measurements did not differ between patients and controls, resistin was clearly associated with general inflammation, renal disease, treatment with glucocorticosteroids, and bone loss. We hypothesize that resistin has proinflammatory and disease-promoting properties in SLE. Further studies are needed to elucidate the mechanism behind these associations.
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| 18. |
- Amu, Sylvie, 1978, et al.
(författare)
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CD25-expressing B-lymphocytes in rheumatic diseases
- 2007
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Ingår i: Scand J Immunol. - : Wiley. - 0300-9475. ; 65:2, s. 182-91
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Tidskriftsartikel (refereegranskat)abstract
- B cells play an important role in the development of autoimmune diseases due to their production of autoantibodies, antigen-presenting capacity and production of pro-inflammatory cytokines. The purpose of the present study was to analyse B cells from rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients, with respect to their expression of the IL-2 receptor (IL-2R) subunit CD25. Using flow cytometry, we found that CD25(+) B cells from RA patients expressed significantly higher frequencies of CD122 and CD132 than CD25(+) B cells from control subjects, indicating a fully functional IL-2R. These CD25(+) B cells also expressed higher frequencies of the co-stimulatory molecule CD80, whereas IgM and IgA expression was decreased compared with CD25(+) B cells from healthy controls. In addition B cells from SLE patients co-expressed CD25 together with CD80, CD122, and CD132, but to a lower degree IgD and IgM, when compared with healthy controls. Taken together, our results indicate that CD25(+) B cells from RA and SLE patients are in a highly activated state, display a more mature phenotype and suggest that this B cell subset may be involved in the pathogenesis of RA and SLE.
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| 19. |
- Amu, Sylvie, 1978, et al.
(författare)
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The Human Immunomodulatory CD25(+) B Cell Population belongs to the Memory B Cell Pool
- 2007
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Ingår i: Scand J Immunol. - 0300-9475. ; 66:1, s. 77-86
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Tidskriftsartikel (refereegranskat)abstract
- We have shown that human CD20(+)25(+) B cells display immunomodulatory properties. The aim of this study was to investigate if CD25(+) B cells are found within the CD27 memory B cell population, and to analyse pattern of their cytokine production. B cells isolated from healthy subjects, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients were analysed regarding the frequency of CD25(+) B cells within certain B cell subsets. Purified CD25(+) B cells from healthy subject were used in vitro to evaluate their production of immunomodulatory cytokines. In healthy subjects the majority (60%) of memory B cells (CD20(+)27(+)) also co-expressed CD25 while only 10-20% of the naive B cells (CD20(+)27(-)) and plasmablasts (CD20-27(+)) expressed CD25. In RA and SLE patients, we found that 51% and 48%, respectively, co-expressed CD25 in the memory population, whereas only 11% and 9% co-expressed CD25 in the naive B cell population. Phenotypic analysis of the CD20(+)25(+)27(+) and CD20(+)25(+)27(-) cells using CD10, CD24, CD38, CD45, CD71, CD80, CD86, CD95, CD138, BAFF-R, TACI, IgA, IgD, IgG and IgM showed that CD20(+)25(+)27(+) B cells preferentially represent highly activated, Ig class switched memory B cells. Cytokine profile analysis showed that CD25(+) B cells secreted significantly higher levels of IL-10 versus CD25(-) B cells. In contrast, TGF-beta1 secretion was similar between the CD25(+) and CD25(-) sub-populations. In conclusion, CD20(+)25(+) B cells constitute a unique subpopulation preferentially occurring among CD20(+)27(+) memory B cells. We suggest that CD25 can be used as a marker for a memory B cell subset.
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| 20. |
- Andersson, Karin, 1972, et al.
(författare)
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Down-regulation of survivin alleviates experimental arthritis.
- 2015
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Ingår i: Journal of leukocyte biology. - 1938-3673. ; 97:1, s. 135-45
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Tidskriftsartikel (refereegranskat)abstract
- Survivin is a proto-oncogene that regulates cell division and apoptosis. It is a molecular marker of cancer. Recently, survivin has emerged as a feature of RA, associated with severe joint damage and poor treatment response. The present study examined if inhibition of survivin affects experimental arthritis, which was induced in mBSA-immunized mice by an injection of mBSA in the knee joint or developed spontaneously in collagen type II-immunized mice. The inhibition of survivin transcription by a lentivirus shRNA construct alleviated joint inflammation and reduced bone damage. The inhibition of survivin reduced the levels of metalloproteinases, β-catenin, and vimentin, limiting the invasive capacity of synovia, while no inhibition of osteoclastogenesis could be found. The inhibition of survivin led to a p53-independent reduction of T cell proliferation and favored the transcription and activity of Blimp-1, which limited IL-2 production and facilitated formation of regulatory Foxp3(+)CD4(+) and effector CD8(+) T cells. The study shows that the inhibition of survivin is sufficient to reduce joint inflammation and bone damage in preclinical models of arthritis. Antiarthritic effects of survivin inhibition are related to p53-independent control of lymphocyte proliferation.
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| 21. |
- Andersson, Karin, 1972, et al.
(författare)
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Inflammation in the hippocampus affects IGF1 receptor signaling and contributes to neurological sequelae in rheumatoid arthritis.
- 2018
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 115:51
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Tidskriftsartikel (refereegranskat)abstract
- Rheumatoid arthritis (RA) is an inflammatory joint disease with a neurological component including depression, cognitive deficits, and pain, which substantially affect patients' quality of daily life. Insulin-like growth factor 1 receptor (IGF1R) signaling is one of the factors in RA pathogenesis as well as a known regulator of adult neurogenesis. The purpose of this study was to investigate the association between IGF1R signaling and the neurological symptoms in RA. In experimental RA, we demonstrated that arthritis induced enrichment of IBA1+ microglia in the hippocampus. This coincided with inhibitory phosphorylation of insulin receptor substrate 1 (IRS1) and up-regulation of IGF1R in the pyramidal cell layer of the cornus ammoni and in the dentate gyrus, reproducing the molecular features of the IGF1/insulin resistance. The aberrant IGF1R signaling was associated with reduced hippocampal neurogenesis, smaller hippocampus, and increased immobility of RA mice. Inhibition of IGF1R in experimental RA led to a reduction of IRS1 inhibition and partial improvement of neurogenesis. Evaluation of physical functioning and brain imaging in RA patients revealed that enhanced functional disability is linked with smaller hippocampus volume and aberrant IGF1R/IRS1 signaling. These results point to abnormal IGF1R signaling in the brain as a mediator of neurological sequelae in RA and provide support for the potentially reversible nature of hippocampal changes.
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| 22. |
- Andersson, Karin, 1972, et al.
(författare)
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Survivin co-ordinates formation of follicular T-cells acting in synergy with Bcl-6
- 2015
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 6:24, s. 20043-20057
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Tidskriftsartikel (refereegranskat)abstract
- Follicular T helper (Tfh) cells are recognized by the expression of CXCR5 and the transcriptional regulator Bcl-6. Tfh cells control B cell maturation and antibody production, and if deregulated, may lead to autoimmunity. Here, we study the role of the proto-oncogene survivin in the formation of Tfh cells. We show that blood Tfh cells of patients with the autoimmune condition rheumatoid arthritis, have intracellular expression of survivin. Survivin was co-localized with Bcl-6 in the nuclei of CXCR5(+)CD4 lymphocytes and was immunoprecipitated with the Bcl-6 responsive element of the target genes. Inhibition of survivin in arthritic mice led to the reduction of CXCR5(+) Tfh cells and to low production of autoantibodies. Exposure to survivin activated STAT3 and induced enrichment of PD-1(+)Bcl-6(+) subset within Tfh cells. Collectively, our study demonstrates that survivin belongs to the Tfh cell phenotype and ensures their optimal function by regulating transcriptional activity of Bcl-6.
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| 23. |
- Andersson, Karin, 1972, et al.
(författare)
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Survivin controls biogenesis of microRNA in smokers: A link to pathogenesis of rheumatoid arthritis.
- 2017
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Ingår i: Biochimica et biophysica acta. - : Elsevier BV. - 0006-3002. ; 1863:3, s. 663-673
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Tidskriftsartikel (refereegranskat)abstract
- MicroRNAs (miRs) represent a part of epigenetic control of autoimmunity gaining increasing attention in rheumatoid arthritis (RA). Since cigarette smoking plays important role in RA pathogenesis and reprograms transcriptional profile of miRNAs, we ask if the onco-protein survivin, a novel biomarker of RA, may provide a link between smoking and miRNA. Studying survivin expression in leukocytes of 144 female RA patients we observed that smoking patients had higher survivin transcription and a remarkable spreading of survivin isoforms. This was associated with restricted pattern and low production of miRs. Additionally, miRNA processing enzymes Dicer and DGRC8 were decreased in the patients with survivin isoform spreading. The direct contribution of survivin in miRs biogenesis was confirmed by a massive increase of miRs production following inhibition of survivin in leukocyte cultures. Dicer is shown to mediate these effects of survivin. Chromatin immunoprecipitation analysis demonstrated binding of survivin to the Dicer promoter region. Dicer expression increased 5-folds following survivin inhibition. Taken together, this study presents experimental evidence of a novel cellular function of survivin, control of miRs biogenesis. Up-regulation of survivin in smokers suggests its role as effector of the adverse epigenetic control in RA.
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| 24. |
- Andersson, Sofia E M, 1979, et al.
(författare)
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Activation of Fms-like tyrosine kinase 3 signaling enhances survivin expression in a mouse model of rheumatoid arthritis.
- 2012
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 7:10
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Tidskriftsartikel (refereegranskat)abstract
- Survivin is known as an inhibitor of apoptosis and a positive regulator of cell division. We have recently identified survivin as a predictor of joint destruction in patients with rheumatoid arthritis (RA). Flt3 ligand (Flt3L) is expressed in the inflamed joints and has adjuvant properties in arthritis. Studies on 90 RA patients (median age 60.5 years [range, 24-87], disease duration 10.5 years [range, 0-35]) show a strong positive association between the levels of survivin and Flt3L in blood. Here, we present experimental evidence connecting survivin and Flt3L signaling. Treatment of BALB/c mice with Flt3L led to an increase of survivin in the bone marrow and in splenic dendritic cells. Flt3L changed the profile of survivin splice variants, increasing transcription of the short survivin40 in the bone marrow. Treatment with an Flt3 inhibitor reduced total survivin expression in bone marrow and in the dendritic cell population in spleen. Inhibition of survivin transcription in mice, by shRNA lentiviral constructs, reduced the gene expression of Flt3L. We conclude that expression of survivin is a downstream event of Flt3 signaling, which serves as an essential mechanism supporting survival of leukocytes during their differentiation, and maturation of dendritic cells, in RA.
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| 25. |
- Baboota, Ritesh, et al.
(författare)
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Chronic hyperinsulinemia promotes human hepatocyte senescence
- 2022
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Ingår i: Molecular Metabolism. - : Elsevier BV. - 2212-8778. ; 64
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Cellular senescence, an irreversible proliferative cell arrest, is caused by excessive intracellular or extracellular stress/damage. Increased senescent cells have been identified in multiple tissues in different metabolic and other aging-related diseases. Recently, several human and mouse studies emphasized the involvement of senescence in development and progression of NAFLD. Hyperinsulinemia, seen in obesity, metabolic syndrome, and other conditions of insulin resistance, has been linked to senescence in adipocytes and neurons. Here, we investigate the possible direct role of chronic hyperinsulinemia in the development of senescence in human hepatocytes. Methods: Using fluorescence microscopy, immunoblotting, and gene expression, we tested senescence markers in human hepatocytes subjected to chronic hyperinsulinemia in vitro and validated the data in vivo by using liver-specific insulin receptor knockout (LIRKO) mice. The consequences of hyperinsulinemia were also studied in senescent hepatocytes following doxorubicin as a model of stress-induced senescence. Furthermore, the effects of senolytic agents in insulin- and doxorubicin-treated cells were analyzed. Results: Results showed that exposing the hepatocytes to prolonged hyperinsulinemia promotes the onset of senescence by increasing the expression of p53 and p21. It also further enhanced the senescent phenotype in already senescent hepatocytes. Addition of insulin signaling pathway inhibitors prevented the increase in cell senescence, supporting the direct contribution of insulin. Furthermore, LIRKO mice, in which insulin signaling in the liver is abolished due to deletion of the insulin receptor gene, showed no differences in senescence compared to their wild-type counterparts despite having marked hyperinsulinemia indicating these are receptor-mediated effects. In contrast, the persistent hyperinsulinemia in LIRKO mice enhanced senescence in white adipose tissue. In vitro, senolytic agents dasatinib and quercetin reduced the prosenescent effects of hyperinsulinemia in hepatocytes. Conclusion: Our findings demonstrate a direct link between chronic hyperinsulinemia and hepatocyte senescence. This effect can be blocked by reducing the levels of insulin receptors or administration of senolytic drugs, such as dasatinib and quercetin.
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