12 results on '"Osmundsen H"'
Search Results
2. Enhanced susceptibility to periodontitis in an animal model of depression: reversed by chronic treatment with the anti-depressant tianeptine.
- Author
-
Breivik T, Gundersen Y, Myhrer T, Fonnum F, Osmundsen H, Murison R, Gjermo P, von Hörsten S, and Opstad PK
- Published
- 2006
- Full Text
- View/download PDF
3. Metabolism of erucic acid in perfused rat liver: Increased chain shortening after feeding partially hydrogenated marine oil and rapeseed oil.
- Author
-
Christiansen, E., Thomassen, M., Christiansen, R., Osmundsen, H., and Norum, K.
- Abstract
The metabolism of [14-C] erucic acid was studied in perfused livers from rats fed on diets containing partially hydrogenated marine oil or rapeseed oil for three days or three weeks. Control rats were given groundnut oil. Chain-shortening of erucic acid, mainly to 18∶1, was found in all dietary groups. In the marine oil and rapeseed oil groups, the percentage of chain-shortened fatty acids in very low density lipoproteins-triacylglycerols (VLDL-TG) exported from the liver increased after prolonged feeding. A similar increase was found in liver TG only with partially hydrogenated marine oil. This oil, rich in trans fatty acids, thus seemed to be more effective in promoting chain-shortening. The fatty acid composition of the secreted and stored TG differed both with respect to total fatty acids and radioactively labeled fatty acids, indicating that at least 2 different pools of TG exist in the liver. The lack of lipidosis in livers from rats fed dietary oils rich in 22∶1 fatty acids is discussed in relation to these findings. In conclusion, a discussion is presented expressing the view that the reversal of the acute lipidosis in the hearts of rats fed rapeseed oil or partially hydrogenated marine oils is, to a large extent, derived from the increased chain-shortening capacity of erucic acid in liver. [ABSTRACT FROM AUTHOR]
- Published
- 1979
- Full Text
- View/download PDF
4. HEPATIC PEROXISOMAL PROLIFERATION CAUSED BY ETHYL 2[5(4-CHLORO-PHENYL)PENTYL]OXIRAN-2- CARBOXYLATE (CPOC): A HYPOGLYCEMIC INHIBITOR OF MITOCHONDRIAL FATTY ACID OXIDATION.
- Author
-
Sherratt, H. S. A., Bartlett, K., Koundakjian, P. P., Turnbull, D. M., Osmundsen, H., Hoof, F. Van, and Bone, A. J.
- Published
- 1982
- Full Text
- View/download PDF
5. Effects of fish oil and n-3 fatty acids on the regulation of Δ9-fatty acid desaturase mRNA and -activity in rat liver.
- Author
-
Løchsen, T., Ormstad, H., Braud, H., Brodal, B., Christiansen, E., and Osmundsen, H.
- Published
- 1999
- Full Text
- View/download PDF
6. Expression of Clu and Tgfb1 during murine tooth development: effects of in-vivo transfection with anti-miR-214.
- Author
-
Khan QE, Sehic A, Khuu C, Risnes S, and Osmundsen H
- Subjects
- Animals, Animals, Newborn, Clusterin analysis, Gene Expression Profiling, Immunohistochemistry, Mice, Molar embryology, Oligonucleotide Array Sequence Analysis, Reverse Transcriptase Polymerase Chain Reaction, Tooth Germ embryology, Tooth Germ metabolism, Transfection, Transforming Growth Factor beta1 analysis, Clusterin genetics, Gene Expression Regulation, Developmental, MicroRNAs antagonists & inhibitors, Molar growth & development, Odontogenesis genetics, Tooth Calcification genetics, Tooth Germ growth & development, Transforming Growth Factor beta1 genetics
- Abstract
Expression of clusterin (Clu) in the murine first molar tooth germ was markedly increased at postnatal developmental stages. The time-course of expression of this gene paralleled those of other genes encoding proteins involved during the secretory phase of odontogenesis, as described previously. Immunohistochemical studies of clusterin in murine molar tooth germs suggested this protein to be located in outer enamel epithelium, regressing enamel organ, secretory ameloblasts, and the dental epithelium connecting the tooth to the oral epithelium at an early eruptive stage. Immunolabelling of transforming growth factor beta-1 (TGF-β1) revealed it to be located close to clusterin. The levels of expression of Clu and Tgfb1 were markedly decreased following in-vivo transfection with anti-miR-214. In contrast, the expression of several genes associated with regulation of growth and development were increased by this treatment. We suggest that clusterin has functions during secretory odontogenesis and the early eruptive phase. Bioinformatic analysis after treatment with anti-miR-214 suggested that, whilst cellular activities associated with tooth mineralization and eruption were inhibited, activities associated with an alternative developmental activity (i.e. biosynthesis of contractile proteins) appeared to be stimulated. These changes probably occur through regulation mediated by a common cluster of transcription factors and support suggestions that microRNAs (miRNAs) are highly significant as regulators of differentiation during odontogenesis., (© 2013 Eur J Oral Sci.)
- Published
- 2013
- Full Text
- View/download PDF
7. Expression of delta-like 1 homologue and insulin-like growth factor 2 through epigenetic regulation of the genes during development of mouse molar.
- Author
-
Khan QE, Sehic A, Skalleberg N, Landin MA, Khuu C, Risnes S, and Osmundsen H
- Subjects
- Analysis of Variance, Animals, Calcium-Binding Proteins, Epigenomics, Genomic Imprinting, Insulin-Like Growth Factor II metabolism, Intercellular Signaling Peptides and Proteins metabolism, Mice, Mice, Inbred BALB C embryology, Multigene Family, Odontogenesis physiology, Reverse Transcriptase Polymerase Chain Reaction, Tissue Array Analysis, DNA Methylation physiology, Gene Expression Regulation, Developmental, Insulin-Like Growth Factor II genetics, Intercellular Signaling Peptides and Proteins genetics, Odontogenesis genetics, Tooth Germ growth & development
- Abstract
Delta-like 1 homolog (Dlk1) and insulin-like growth factor 2 (Igf2) are two of six well-studied mouse imprinted gene clusters that are paternally expressed. Their expression is also linked to their maternally expressed non-coding RNAs, encoded by Gene trap locus 2 (Gtl2) and Imprinted maternally expressed transcript (H19), co-located as imprinted gene clusters. Using deoxyoligonucleotide microarrays and real-time RT-PCR analysis we showed Dlk1 and Gtl2 to exhibit a time-course of expression during tooth development that was similar to that of Igf2 and H19. Western blot analysis of proteins encoded by Dlk1 and Igf2 suggested that the levels of these proteins reflected those of the corresponding mRNAs. Immunohistochemical studies of DLK1 in murine molars detected the protein in both epithelial and mesenchymal regions, in developing cusp mesenchyme, and in newly synthesized enamel and dentin tubules. IGF2 protein was detected primarily at prenatal stages, suggesting that it may be active before birth. Analysis of methylation of cytosine-phosphate-guanine (CpG) islands in both Dlk1 and Igf2 suggested the presence of an increasing fraction of hypermethylated bases with increasing time of development. The increased levels of hypermethylation coincided both with the diminished levels of expression of Dlk1 and Igf2 and with decreased levels of DLK1 and IGF2 proteins in the tooth germ, suggesting that their expression is regulated via methylation of CpG islands present in these genes., (© 2012 Eur J Oral Sci.)
- Published
- 2012
- Full Text
- View/download PDF
8. Expression of prion gene and presence of prion protein during development of mouse molar tooth germ.
- Author
-
Khan QE, Press CM, Sehic A, Landin MA, Risnes S, and Osmundsen H
- Subjects
- Adaptor Proteins, Signal Transducing analysis, Ameloblasts cytology, Amelogenesis genetics, Amelogenesis physiology, Amelogenin analysis, Amyloid beta-Protein Precursor analysis, Animals, Animals, Newborn, Blotting, Western, Calcium-Binding Proteins analysis, Clusterin analysis, Dental Enamel embryology, Dental Enamel Proteins analysis, Dental Papilla embryology, Epithelium embryology, Gene Expression Regulation, Developmental genetics, Gestational Age, Immunohistochemistry, Incisor embryology, Mice, Mice, Inbred Strains, Nerve Tissue Proteins analysis, Odontogenesis genetics, Oligonucleotide Array Sequence Analysis, Prion Proteins, Prions analysis, Molar embryology, Odontogenesis physiology, Prions genetics, Tooth Germ embryology
- Abstract
In order to gain insight into possible cellular functions of the prion protein (PrP) during normal development, the expression of Prnp (encoding the PrP) and the distribution of the PrP were studied in murine tooth germs. Expression of Prnp in the mouse first molar tooth germ was highly dynamic, increasing several-fold during the secretory phase of odontogenesis, exhibiting a time-course of expression similar to that of genes coding for other extracellular proteins [e.g. enamel matrix proteins (Amelx, Ambn, Enam), Aplp1, Clstn1, and Clu]. Western blot analysis suggested that the amounts of PrP and amyloid beta (A4) precursor-like protein 1 (APLP1) in the tooth germ followed time-courses similar to those of the corresponding mRNAs. Immunohistochemical studies of the distribution of PrP in murine molar and incisor tooth germs at embryonic day (E)18.5 suggested that this protein was located in the cervical loop, outer enamel epithelium, pre-ameloblasts, and dental papilla. Different degrees of immunolabelling of pre-ameloblasts on the mesial and distal aspects of a lower molar cusp may be related to different enamel configurations on the two aspects. It is concluded that the dynamic patterns of expression of Prnp, and of distribution of PrP, suggest that PrP may have functions during secretory odontogenesis, perhaps in relation to amelogenesis., (© 2010 Eur J Oral Sci.)
- Published
- 2010
- Full Text
- View/download PDF
9. Gene expression and dental enamel structure in developing mouse incisor.
- Author
-
Sehic A, Risnes S, Khan QE, Khuu C, and Osmundsen H
- Subjects
- Actins analysis, Ameloblasts cytology, Amelogenesis genetics, Amelogenin analysis, Animals, Animals, Newborn, Apoptosis genetics, Calbindins, Cell Growth Processes genetics, Cell Movement genetics, Cytoskeleton genetics, Dental Enamel ultrastructure, Dental Enamel Proteins analysis, Gene Expression Profiling, Gene Expression Regulation, Developmental genetics, Gestational Age, Incisor ultrastructure, Kallikreins analysis, Matrix Metalloproteinase 20 analysis, Mice, MicroRNAs analysis, Microscopy, Electron, Scanning, Nerve Tissue Proteins analysis, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, S100 Calcium Binding Protein G analysis, Tooth Germ ultrastructure, Dental Enamel embryology, Incisor embryology, Tooth Germ embryology
- Abstract
At the mouse incisor tip the initially differentiated ameloblasts produce a thin, prism-free enamel, while further apically, in the immediate adjacent segment, the enamel thickness increases and the four-layered enamel of mouse incisor is formed. Comparative gene-expression profiling was carried out on RNA isolated from these two segments of incisor tooth germs at embryonic day (E)17.5 and at postnatal days (P)0, 1, 2, and 10 using microarrays to measure messenger RNA (mRNA) and microRNA (miRNA) species present in the segments. Validation of expression data was achieved using real-time reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Bioinformatic data suggested enhanced cellular apoptosis in the incisal tip segment, which, together with diminished expression of the Amelx and Enam genes, may contribute to the production of the thin enamel seen in this tooth segment. For genes exhibiting higher levels of expression in the adjacent segment where complex enamel is being formed, bioinformatic analysis suggested significant associations with cellular functions involving the actin cytoskeleton, cellular development, morphology, and movement. This is suggested to reflect that ameloblasts with Tomes' process are being organized in transverse rows, facilitating the transverse movement that results in prism decussation in the inner enamel of the adjacent segment. Bioinformatic analysis of miRNA expression data lends support to these suggestions.
- Published
- 2010
- Full Text
- View/download PDF
10. Signal transduction and gene transcription induced by TFF3 in oral keratinocytes.
- Author
-
Storesund T, Schenck K, Osmundsen H, Røed A, Helgeland K, and Kolltveit KM
- Subjects
- Cell Death drug effects, Cell Movement drug effects, Cell Proliferation drug effects, Cell Survival drug effects, Cells, Cultured, DNA-Binding Proteins drug effects, Down-Regulation drug effects, Genes, Immediate-Early drug effects, Genes, fos drug effects, Humans, JNK Mitogen-Activated Protein Kinases analysis, Keratinocytes enzymology, Male, Mitogen-Activated Protein Kinase 1 analysis, Mitogen-Activated Protein Kinase 3 analysis, Mouth Mucosa enzymology, Oligonucleotide Array Sequence Analysis, Peptides analysis, Phosphatidylinositol 3-Kinases analysis, Phosphoproteins analysis, Proto-Oncogene Proteins c-akt analysis, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, Transcription Factors drug effects, Trefoil Factor-2, Up-Regulation drug effects, Young Adult, p38 Mitogen-Activated Protein Kinases analysis, Keratinocytes drug effects, Mouth Mucosa drug effects, Peptides pharmacology, Signal Transduction drug effects, Transcription, Genetic drug effects
- Abstract
Trefoil factor family 3 (TFF3) is secreted in saliva. The peptide improves the mechanical and chemical resistance of mucins, and it may act as a motility signal for oral keratinocytes during wound healing. This study aimed to identify novel functions of TFF3 in oral keratinocytes. To achieve this, we used phosphoprotein and messenger RNA (mRNA) arrays to compare TFF3-treated and untreated oral keratinocytes. Analysis of the phosphoprotein array indicated that TFF3 signals through the mitogen-activated protein kinases (MAPKs) c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK1/2), and through the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB) pathway. Microarray analysis of mRNA showed that TFF3 stimulation induced changes in the expression of genes functionally related to cell death/survival, cell growth and proliferation, and cell movement. The reverse transcription-polymerase chain reaction (RT-PCR) results indicated that the transcription of some immediate-early genes (IEGs) was downregulated, whereas the IEGs FBJ osteosarkoma oncogene (FOS) and C-MYC binding protein (MYCBP2) were transiently upregulated by TFF3 stimulation. Together, the results of the arrays indicate that TFF3 is a modifying factor in pathways regulating cell survival, cell growth and proliferation, and cell migration of oral keratinocytes. Trefoil factor family 3 may therefore promote oral wound healing and it should be considered for the treatment of oral ulcerating diseases, or of other diseases.
- Published
- 2009
- Full Text
- View/download PDF
11. Neonatal dexamethasone and chronic tianeptine treatment inhibit ligature-induced periodontitis in adult rats.
- Author
-
Breivik T, Gundersen Y, Osmundsen H, Fonnum F, and Opstad PK
- Subjects
- Age Factors, Alveolar Bone Loss prevention & control, Animals, Animals, Newborn, Anti-Inflammatory Agents administration & dosage, Antidepressive Agents, Tricyclic administration & dosage, Dexamethasone administration & dosage, Dexamethasone analogs & derivatives, Disease Susceptibility, Down-Regulation, Glucocorticoids administration & dosage, Gram-Negative Bacteria immunology, Hypothalamo-Hypophyseal System drug effects, Hypothalamo-Hypophyseal System immunology, Lipopolysaccharides immunology, Periodontitis immunology, Pituitary-Adrenal System drug effects, Pituitary-Adrenal System immunology, Rats, Rats, Wistar, Thiazepines administration & dosage, Transforming Growth Factor beta blood, Transforming Growth Factor beta1, Tumor Necrosis Factor-alpha analysis, Anti-Inflammatory Agents therapeutic use, Antidepressive Agents, Tricyclic therapeutic use, Dexamethasone therapeutic use, Glucocorticoids therapeutic use, Periodontitis prevention & control, Thiazepines therapeutic use
- Abstract
Objective: The responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis has been found to play a significant role for susceptibility and resistance to periodontal disease. In the present study we have investigated the effects of two different treatment strategies, which have been found to down-regulate the HPA axis, on ligature-induced periodontitis., Methods: In experiment 1, newborn rats were treated with the synthetic glucocorticoid hormone dexamethasone-21-phosphate, which permanently down-regulates HPA axis responsiveness. In experiment 2, adult rats were treated with the novel antidepressant drug tianeptine, which opposes the action of stress. Periodontitis was inflicted upon all rats. Just before decapitation the animals received gram-negative bacterial lipopolysaccharide (LPS) to induce a robust immune and HPA axis response., Results: Compared to the saline-treated control rats, dexamethasone-treated rats had significantly less periodontal bone loss (p < 0.01), reduced expression of glucocorticoid receptors in the hippocampus (p < 0.001), lower corticosterone (p=0.01) and higher plasma levels of the cytokine tumor necrosis factor (TNF)-alpha (p < 0.05) after LPS challenge. Also the tianeptine-treated rats showed significantly reduced periodontal bone loss (p=0.01), enhanced plasma levels of TNF-alpha (p < 0.05), and transforming growth factor-1beta (p < 0.01), whereas no significant difference was found in corticosterone levels., Conclusion: An individual's responsiveness to danger signals, whether they are of immunological, chemical, or psychological origin, may be an important factor for explaining variability in susceptibility to periodontal disease. The results may provide new insight into the mechanisms of periodontal disease development, and open new vistas for disease prevention.
- Published
- 2006
- Full Text
- View/download PDF
12. Chronic treatment with the glutamate receptor antagonist MK-801 alters periodontal disease susceptibility.
- Author
-
Breivik T, Gundersen Y, Osmundsen H, Opstad PK, and Fonnum F
- Subjects
- Animals, Corticosterone blood, Disease Susceptibility, Drug Evaluation, Preclinical, Hypothalamo-Hypophyseal System drug effects, Male, Periodontal Diseases blood, Periodontal Diseases prevention & control, Pituitary-Adrenal System drug effects, Rats, Rats, Inbred F344, Receptors, Glucocorticoid blood, Reverse Transcriptase Polymerase Chain Reaction, Tumor Necrosis Factor-alpha analysis, Dizocilpine Maleate therapeutic use, Excitatory Amino Acid Antagonists therapeutic use, Periodontal Diseases drug therapy
- Abstract
Objective: Previous experiments in rats suggest that hypothalamic-pituitary-adrenal (HPA) axis over-responsiveness, which leads to increased secretion of immunoregulatory glucocorticoid hormones, increases periodontal disease susceptibility, whereas HPA axis under-responsiveness is associated with increased resistance to the disease. The present study was designed to investigate whether MK-801 (dizocilipine malate), an antagonist of the glutamate receptor N-methyl-D-aspartate (NMDA) in the brain, which has been found to play an important role in the regulation of the HPA axis, would influence the outcome of experimental ligature-induced periodontal disease in a rat model., Methods: Experimental periodontal disease was induced in periodontal disease susceptible and HPA axis high-responding Fischer 344 rats 2 days before chronic treatment with MK-801(1 mg/kg intraperitoneally). The periodontal breakdown was assessed after the ligatures had been in place for 23 days. Following intraperitoneal Gram-negative bacterial lipopolysaccharide stimulation (Escherichia coli, 250 microg/kg), concentrations of glucocorticoid receptors (GRs) in the hippocampus, and levels of the cytokine tumour necrosis factor alpha (TNF-alpha), as well as the HPA axis-derived hormone corticosterone, were measured in serum., Results: Compared to vehicle-treated controls, MK-801-treated rats had significantly increased periodontal tissue destruction (p < 0.01). MK-801-treated rats also showed significantly increased expression of GRs in the hippocampus (p < 0.05), elevated levels of corticosterone (p < 0.001) and reduced levels of TNF-alpha (p < 0.01) in serum 2 h after lipopolysaccharide stimulation., Conclusion: These findings may implicate glutamate receptor-dependent mechanisms in periodontal disease, and support the concept of a bidirectional immune-brain-immune regulatory network with importance for periodontal health and disease.
- Published
- 2005
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.