| 1. |
- Amzaleg, Y., et al.
(författare)
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Estrogens and selective estrogen receptor modulators differentially antagonize Runx2 in ST2 mesenchymal progenitor cells
- 2018
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Ingår i: Journal of Steroid Biochemistry and Molecular Biology. - : Elsevier BV. - 0960-0760 .- 1879-1220. ; 183, s. 10-17
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Tidskriftsartikel (refereegranskat)abstract
- Estrogens attenuate bone turnover by inhibiting both osteoclasts and osteoblasts, in part through antagonizing Runx2. Apparently conflicting, stimulatory effects in osteoblast lineage cells, however, sway the balance between bone resorption and bone formation in favor of the latter. Consistent with this dualism, 17 beta-estradiol (E2) both stimulates and inhibits Runx2 in a locus-specific manner, and here we provide evidence for such locus specific regulation of Runx2 by E2 in vivo. We also demonstrate dual, negative and positive, regulation of Runx2-driven alkaline phosphatase (ALP) activity by increasing E2 concentrations in ST2 osteoblast progenitor cells. We further compared the effects of E2 to those of the Selective Estrogen Receptor Modulators (SERMs) raloxifene (ral) and lasofoxifene (las) and the phytoestrogen puerarin. We found that E2 at the physiological concentrations of 0.1-1 nM, as well as ral and las, but not puerarin, antagonize Runx2-driven ALP activity. At >= 10 nM, E2 and puerarin, but not ral or las, stimulate ALP relative to the activity measured at 0.1-1 nM. Contrasting the difference between E2 and SERMs in ST2 cells, they all shared a similar dose-response profile when inhibiting preosteoclast proliferation. That ral and las poorly mimic the locus-and concentration-dependent effects of E2 in mesenchymal progenitor cells may help explain their limited clinical efficacy.
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| 2. |
- Austin, Thomas R, et al.
(författare)
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Large-scale circulating proteome association study (CPAS) meta-analysis identifies circulating proteins and pathways predicting incident hip fractures.
- 2024
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - 1523-4681. ; 39:2, s. 139-149
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Tidskriftsartikel (refereegranskat)abstract
- Hip fractures are associated with significant disability, high cost, and mortality. However, the exact biological mechanisms underlying susceptibility to hip fractures remain incompletely understood. In an exploratory search of the underlying biology as reflected through the circulating proteome, we performed a comprehensive Circulating Proteome Association Study (CPAS) meta-analysis for incident hip fractures. Analyses included 6430 subjects from two prospective cohort studies (Cardiovascular Health Study and Trøndelag Health Study) with circulating proteomics data (aptamer-based 5K SomaScan version 4.0 assay; 4979 aptamers). Associations between circulating protein levels and incident hip fractures were estimated for each cohort using age and sex-adjusted Cox regression models. Participants experienced 643 incident hip fractures. Compared with the individual studies, inverse-variance weighted meta-analyses yielded more statistically significant associations, identifying 23 aptamers associated with incident hip fractures (conservative Bonferroni correction 0.05/4979, P<1.0×10-5). The aptamers most strongly associated with hip fracture risk corresponded to two proteins of the growth hormone/insulin growth factor system (GHR and IGFBP2), as well as GDF15 and EGFR. High levels of several inflammation-related proteins (CD14, CXCL12, MMP12, ITIH3) were also associated with increased hip fracture risk. Ingenuity pathway analysis identified reduced LXR/RXR activation and increased acute phase response signaling to be overrepresented among those proteins associated with increased hip fracture risk. These analyses identified several circulating proteins and pathways consistently associated with incident hip fractures. These findings underscore the usefulness of the meta-analytic approach for comprehensive CPAS in a similar manner as has previously been observed for large-scale human genetic studies. Future studies should investigate the underlying biology of these potential novel drug targets.
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| 3. |
- Jansson, John-Olov, 1954, et al.
(författare)
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Body weight homeostat that regulates fat mass independently of leptin in rats and mice.
- 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. ; 115:2, s. 427-432
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Tidskriftsartikel (refereegranskat)abstract
- Subjects spending much time sitting have increased risk of obesity but the mechanism for the antiobesity effect of standing is unknown. We hypothesized that there is a homeostatic regulation of body weight. We demonstrate that increased loading of rodents, achieved using capsules with different weights implanted in the abdomen or s.c. on the back, reversibly decreases the biological body weight via reduced food intake. Importantly, loading relieves diet-induced obesity and improves glucose tolerance. The identified homeostat for body weight regulates body fat mass independently of fat-derived leptin, revealing two independent negative feedback systems for fat mass regulation. It is known that osteocytes can sense changes in bone strain. In this study, the body weight-reducing effect of increased loading was lost in mice depleted of osteocytes. We propose that increased body weight activates a sensor dependent on osteocytes of the weight-bearing bones. This induces an afferent signal, which reduces body weight. These findings demonstrate a leptin-independent body weight homeostat ("gravitostat") that regulates fat mass.
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| 4. |
- Moro, Elena, et al.
(författare)
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Long-Term Results of a Multicenter Study on Subthalamic and Pallidal Stimulation in Parkinson's Disease
- 2010
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Ingår i: Movement Disorders. - : Wiley. - 0885-3185. ; 25:5, s. 578-586
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Tidskriftsartikel (refereegranskat)abstract
- We report the 5 to 6 year follow-up of a multicenter study of bilateral subthalamic nucleus (STN) and globus pallidus internus (GPi) deep brain stimulation (DBS) in advanced Parkinson's disease (PD) patients. Thirty-live STN patients and 16 GPi patienis were assessed at 5 to 6 years after DBS surgery. Primary outcome measure was the stimulation effect on the motor Unified Parkinson's Disease Rating Scale (UPDRS) assessed with a prospective cross-over double-blind assessment without medications (stimulation was randomly switched on or off). Secondary outcomes were motor UPDRS changes with unblinded assessments in off- and on-medication states with and without stimulation, activities of daily living (ADL), anti-PD medications, and dyskinesias. In double-blind assessment, both STN and GPi DBS were significantly effective in improving the motor UPDRS scores (STN. P < 0.0001, 45.4%; GPi, P = 0.008, 20.0%) compared with of regardless of the sequence of stimulation. In open assessment. both STN- and GPi-DBS significantly improved the off-medication motor UPDRS when compared with before surgery (STN. P < 0.001, 50.5%; GPi, P = 0.002, 35.6%). Dyskinesias and ADL were significantly improved in both groups. Anti-PD medications were significantly reduced only in the STN group. Adverse events were more frequent in the STN group. These results confirm the long-term efficacy of STN and GPi DBS advanced PD. Although the surgical targets were not randomized, there was a trend to 1 better outcome of motor signs in the STN-DBS patients and fewer adverse events in the GPi-DBS group. (C) 2010 Movement Disorder Society
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| 5. |
- Staines, K. A., et al.
(författare)
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Conditional deletion of E11/podoplanin in bone protects against load-induced osteoarthritis
- 2019
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Ingår i: Bmc Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundSubchondral bone (SCB) thickening is one of the earliest detectable changes in osteoarthritic joints and is considered a potential trigger for subsequent articular cartilage degeneration. In this manuscript, we examine whether disruption to the SCB osteocyte network contributes to the initiation and pathogenesis of osteoarthritis.MethodsWe examined expression patterns of the glycoprotein E11/podoplanin by immunohistochemical labelling in murine, human and canine osteoarthritis models. We also examined the effects of twice-weekly administration of Bortezomib, a proteasome inhibitor which stabilises osteocyte E11 levels, to C57/BL6 wild-type male mice (1mg/kg/day) for 8weeks after surgical destabilisation of the medial meniscus. By inducing osteoarthritis-like changes in the right knee joint of 12-week-old male E11 hypomorphic mice (and corresponding controls) using a post-traumatic joint loading model, we also investigated whether a bone-specific E11 deletion in mice increases joint vulnerability to osteoarthritis. Articular cartilage degradation and osteophyte formation were assessed by histology and in line with the OARSI grading system.ResultsOur studies reveal increased E11 expression in osteocytes of human and canine osteoarthritic SCB. We found that Bortezomib administration had no effect on surgically-induced osteoarthritis, potentially due to a lack of the expected stabilisation of E11 in the SCB. We also found, in concordance with our previous work, wild-type mice exhibited significant load-induced articular cartilage lesions on the lateral femoral condyle (p<0.01) and osteophyte formation. In contrast, E11 hypomorphic mice did not develop osteophytes or any corresponding articular lesions.ConclusionsOverall, these data suggest that an intact osteocyte network in the SCB contributes to the development of mechanically-driven osteoarthritis. Further, the data presented here indicate that the molecular pathways that preserve the osteocyte network, such as those driven by E11, may be targeted to limit osteoarthritis pathogenesis.
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| 6. |
- Vallet, M., et al.
(författare)
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Targeted Inactivation of Rin3 Increases Trabecular Bone Mass by Reducing Bone Resorption and Favouring Bone Formation
- 2021
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 109:1, s. 92-102
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Tidskriftsartikel (refereegranskat)abstract
- Common genetic variants at the RIN3 locus on chromosome 14q32 predispose to Paget's disease of bone (PDB) but the mechanisms by which they do so are unknown. Here, we analysed the skeletal phenotype of female mice with targeted inactivation of the mouse Rin3 gene (Rin3(-/-)) as compared with wild-type littermates. The Rin3(-/-) mice had higher trabecular bone volume (BV/TV%) compared with wild type. Mean +/- standard deviation values at the distal femur at 8 weeks were 9.0 +/- 2.5 vs. 7.0 +/- 1.5 (p = 0.002) and at 52 weeks were 15.8 +/- 9.5 vs. 8.5 +/- 4.2 (p = 0.002). No differences were observed in femoral cortical bone parameters with the exception of marrow diameter which was significantly smaller in 52-week-old Rin3(-/-) mice compared to wild type: (0.43 mm +/- 0.1 vs. 0.57 mm +/- 0.2 (p = 0.001). Bone histomorphometry showed a lower osteoclast surface / bone surface (Oc.S/BS%) at 8 weeks in Rin3(-/-) mice compared to wild type (24.1 +/- 4.7 vs. 29.7 +/- 6.6; p = 0.025) but there were no significant differences in markers of bone formation at this time. At 52 weeks, Oc.S/BS did not differ between genotypes but single labelled perimeter (SL.Pm/B.Pm (%)) was significantly higher in Rin3(-/-) mice (24.4 +/- 6.4 vs. 16.5 +/- 3.8, p = 0.003). We conclude that Rin3 negatively regulates trabecular bone mass in mice by inhibiting osteoclastic bone resorption and favouring bone formation. Our observations also suggest that the variants that predispose to PDB in humans probably do so by causing a gain-in-function of RIN3.
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| 7. |
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| 8. |
- Knudsen, Lisbeth E., et al.
(författare)
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Nordic symposium on toxicology and pharmacology without animal experiments-Will it be possible in the next 10 years?
- 2019
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Ingår i: Basic & Clinical Pharmacology & Toxicology. - : Wiley. - 1742-7835 .- 1742-7843. ; 124:5, s. 560-567
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Forskningsöversikt (refereegranskat)abstract
- Toxicological and pharmacological information from human cells and tissues provides knowledge readily applicable to human safety assessment and to the efficacy assessment of pharmaceuticals. The 3R principle in animal studies includes the use of human material in the R of Replacement. The Reduction and Refinement Rs are related to animal use. Knowledge of the 3Rs and successful 3R methods are a prerequisite for the Reduction of animal experiments in the future. More collaboration among researchers using experimental animals and those working in vitro is necessary with mutual respect. The OECD Guidelines for the Testing of Chemicals have included the animal-free part of the 3Rs in guidances for the development and reporting of Adverse Outcome Pathways (AOPs), which is to be part of the Integrated Approaches to Testing and Assessment (IATA). The 3R centres established to help fulfil the Directive 2010/63/EU play an important role to promote the 3Rs and in the development of animal-free toxicology. Research centres in each Nordic country are founded upon solid research activities in cell and organ toxicity, including major EU programmes to promote 3Rs and implementation of good practices and methods broadly in all stakeholders of industry, regulators and academia. In the light of this, the Nordic Symposium on Toxicology and Pharmacology without Animal Experiments addressed more adopted/modified test guidelines or new test guidelines for new end-points, or hazard challenges, new in vitro 3D models, speeding up transfer of knowledge from research to regulation to understand AOP and towards IATA.
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| 9. |
- Merlo, Domenico Franco, et al.
(författare)
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Micronuclei in Cord Blood Lymphocytes and Associations with Biomarkers of Exposure to Carcinogens and Hormonally Active Factors, Gene Polymorphisms, and Gene Expression : The NewGeneris Cohort
- 2014
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Ingår i: Journal of Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 122:2, s. 193-200
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Tidskriftsartikel (refereegranskat)abstract
- Background: Leukemia incidence has increased in recent decades among European children, -suggesting that early-life environmental exposures play an important role in disease development. Objectives: We investigated the hypothesis that childhood susceptibility may increase as a result of in utero exposure to carcinogens and hormonally acting factors. Using cord blood samples from the NewGeneris cohort, we examined associations between a range of biomarkers of carcinogen exposure and hormonally acting factors with micronuclei (MN) frequency as a proxy measure of cancer risk. Associations with gene expression and genotype were also explored. Methods: DNA and protein adducts, gene expression profiles, circulating hormonally acting factors, and GWAS (genome-wide association study) data were investigated in relation to genomic damage measured by MN frequency in lymphocytes from 623 newborns enrolled between 2006 and 2010 across Europe. Results: Malondialdehyde DNA adducts (M(1)dG) were associated with increased MN frequency in binucleated lymphocytes (MNBN), and exposure to androgenic, estrogenic, and dioxin-like compounds was associated with MN frequency in mononucleated lymphocytes (MNMONO), although no monotonic exposure-outcome relationship was observed. Lower frequencies of MNBN were associated with a 1-unit increase expression of PDCD11, LATS2, TRIM13, CD28, SMC1A, IL7R, and NIPBL genes. Gene expression was significantly higher in association with the highest versus lowest category of bulky and M(1)dG-DNA adducts for five and six genes, respectively. Gene expression levels were significantly lower for 11 genes in association with the highest versus lowest category of plasma AR CALUX (R) (chemically activated luciferase expression for androgens) (8 genes), ER alpha CALUX (R) (for estrogens) (2 genes), and DR CALUX (R) (for dioxins). Several SNPs (single-nucleotide polymorphisms) on chromosome 11 near FOLH1 significantly modified associations between androgen activity and MNBN frequency. Polymorphisms in EPHX1/ 2 and CYP2E1 were associated with MNBN. Conclusion: We measured in utero exposure to selected environmental carcinogens and circulating hormonally acting factors and detected associations with MN frequency in newborns circulating T lymphocytes. The results highlight mechanisms that may contribute to carcinogen-induced leukemia and require further research.
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| 10. |
- Ohlsson, Claes, 1965, et al.
(författare)
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Inducible Wnt16 inactivation: WNT16 regulates cortical bone thickness in adult mice.
- 2018
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Ingår i: The Journal of endocrinology. - 1479-6805. ; 237:2, s. 113-122
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Tidskriftsartikel (refereegranskat)abstract
- Substantial progress has been made in the therapeutic reduction of vertebral fracture risk in patients with osteoporosis, but non-vertebral fracture risk has been improved only marginally. Human genetic studies demonstrate that the WNT16 locus is a major determinant of cortical bone thickness and non-vertebral fracture risk and mouse models with life-long Wnt16 inactivation revealed that WNT16 is a key regulator of cortical thickness. These studies, however, could not exclude that the effect of Wnt16 inactivation on cortical thickness might be caused by early developmental and/or growth effects. To determine the effect of WNT16 specifically on adult cortical bone homeostasis, Wnt16 was conditionally ablated in young adult and old mice through tamoxifen-inducible Cre-mediated recombination using CAG-Cre-ER; Wnt16flox/flox (Cre-Wnt16flox/flox) mice. First, 10-week-old Cre-Wnt16flox/flox and Wnt16flox/flox littermate control mice were treated with tamoxifen. Four weeks later, Wnt16 mRNA levels in cortical bone were reduced and cortical thickness in femur was decreased in Cre-Wnt16flox/flox mice compared to Wnt16flox/flox mice. Then, inactivation of Wnt16 in 47-week-old mice (evaluated four weeks later) resulted in a reduction of Wnt16 mRNA levels, cortical thickness and cortical bone strength with no effect on trabecular bone volume fraction. Mechanistic studies demonstrated that the reduced cortical bone thickness was caused by a combination of increased bone resorption and reduced periosteal bone formation. In conclusion, WNT16 is a crucial regulator of cortical bone thickness in young adult and old mice. We propose that new treatment strategies targeting the adult regulation of WNT16 might be useful to reduce fracture risk at cortical bone sites.
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