| 1. |
- Amandusson, Åsa, et al.
(författare)
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Colocalization of oestrogen receptor immunoreactivity and preproenkephalin mRNA expression fo neurons in the superficial laminae of the spinal and medullary dorsal horn of rats
- 1996
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Ingår i: Eur J Neurosci. - : Wiley InterScience. ; 8:11, s. 2440-2445
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Tidskriftsartikel (refereegranskat)abstract
- A double-labelling procedure combining immunohistochemical staining with in situ hybridization using a radiolabelled cRNA probe was employed to demonstrate oestrogen receptor-like immunoreactivity and preproenkephalin-A mRNA in the medullary and spinal dorsal horn of female rats. Both markers labelled large numbers of neurons in the substantia gelatinosa and its trigeminal homologue. Many of these neurons were double-labelled, displaying both oestrogen receptor-like-immunoreactivity and preproenkephalin-A mRNA; cell counts showed that 40-60% of the of the oestrogen receptor-like-immunoreactive cells in the superficial laminae also were labelled for preproenkephalin-A mRNA, and that 60-70% of the preproenkephalin-A mRNA-labelled neurons in the same laminae displayed oestrogen receptor-like immunoreactivity. Previous studies have shown that oestrogen receptors can bind to the promoter region of the preproenkephalin-A gene, and studies on the hypothalamus have demonstrated that oestrogen regulates enkephalin expression in select neuronal populations. The present results demonstrate that enkephalinergic neurons in the superficial dorsal horn contain oestrogen receptors and suggest that oestrogen may play an important role in the modulation of sensory and nociceptive processing in the lower medulla and spinal cord.
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| 2. |
- Amandusson, Åsa, 1974-, et al.
(författare)
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Estrogen-induced alterations of spinal cord enkephalin gene expression
- 1999
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Ingår i: Pain. - : Elsevier. - 0304-3959 .- 1872-6623. ; 83:2, s. 243-248
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Tidskriftsartikel (refereegranskat)abstract
- Enkephalin-synthesizing neurons in the super®cial laminae of the spinal and trigeminal dorsal horn are critical components of the endogenous pain-modulatory system. We have previously demonstrated that these neurons display intracellular estrogen receptors, suggesting that estrogen can potentially influence their enkephalin expression. By using Northern blot, we now show that a bolus injection of estrogen results in a rapid increase in spinal cord enkephalin mRNA levels in ovariectomized female rats. Thus, 4 h after estrogen administration the enkephalin mRNA-expression in the lumbar spinal cord was on average 68% higher (P , 0:05) than in control animals injected with vehicle only. A small increase in the amount of enkephalin mRNA was also seen after 8 h (P , 0:05), whereas no difference between estrogen-injected and control animals was found after 24 h or at time periods shorter than 4 h. Taken together with the previous anatomical data, the present findings imply that estrogen has an acute effect on spinal opioid levels in areas involved in the transmission of nociceptive information.
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| 3. |
- Amandusson, Åsa, 1974-
(författare)
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Estrogen receptor expression in relation to pain modulation and transmission : experimental studies in rats
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Estrogens have a remarkably wide range of actions in the mammalian brain. They not only play a pivotal role in reproductive behavior and sexual differentiation, but also contribute to e.g. thermoregulation, feeding, memory, neuronal survival and the perception of somatosensory stimuli. A multitude of studies on both animals and human subjects has demonstrated potential effects of gonadal hormones, such as estrogens, on pain transmission. These effects most likely involve multiple neuroanatomical circuits as well as diverse neurochemical systems and therefore need to be evaluated specifically in relation to the localization and intrinsic characteristics of the neurons engaged. The overall aim of this thesis is to gain specific knowledge of the possible cellular mechanisms by which estrogens may influence the transmission of nociceptive stimuli at the level of the spinal cord. The estrogen receptors, by which estrogens regulate non-genomic as well as genomic mechanisms, are crucial to estrogen signaling in general and essential to the estrogen-induced effects in the brain. In Paper I, we use immunohistochemistry to label neurons containing estrogen receptor-! (ERα) in the medullary and spinal dorsal horn of female rats. Large numbers of ER!-expressing neurons were found in lamina I and lamina II, i.e. in the areas involved in the processing of primary afferent nociceptive information. This distribution in part overlaps that of enkephalin, a potent pain-inhibiting endogenous opioid. The effects of gonadal hormones on pain modulation may, to a great extent, be blocked by the opioid antagonist naloxone, suggesting an involvement of the endogenous opioid system in the prosecution of hormonal pain regulation. By combining immunohistochemical labeling of ERα with in situ hybridization of preproenkephalin mRNA (Paper II), we demonstrate that the majority of enkephalinergic neurons in the superficial laminae of the spinal and medullary dorsal horn express ER!. This co-localization and the fact that the preproenkephalin gene contains a sequence that binds ERs, suggest that estrogens may potentially regulate enkephalin expression in these cells. This is further supported by the findings in Paper III in which we show that a single subcutaneous injection of estradiol induces a significant increase (on average 68%) in preproenkephalin mRNA content in the spinal cord after 4 hours. The expression of the enkephalin gene in the spinal cord is thus sensitive to fluctuating estradiol levels. In Paper IV, a noxious injection of formalin is used to induce activation of a neuronal population involved in nociceptive transmission from the face. By using a dual-labeling immunohistochemistry protocol, we were able to identify ER!-expressing cells within this neuronal population suggesting that nociceptive-responsive neurons in the medullary dorsal horn express ER!. In all, our findings provide morphological as well as biochemical evidence in support for an estrogen-dependent modulation of nociceptive processing at the level of the dorsal horn.
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| 4. |
- Amandusson, Åsa, et al.
(författare)
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Estrogen receptor-like immunoreactivity in the medullary and spinal dorsal horn of the female rat
- 1995
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Ingår i: Neuroscience Letters. - 0304-3940 .- 1872-7972. ; 196:1-2, s. 25-28
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Tidskriftsartikel (refereegranskat)abstract
- Using an immunohistochemical technique, we demonstrate that large numbers of neurons in the laminar spinal trigeminal nucleus and spinal gray matter of the female rat express estrogen receptors (ER). Densely packed ER-immunoreactive neurons were present in lamina II, but labeled neurons were also present in lamina I, the neck of the dorsal horn, and in lamina X. Labeling was present throughout the length of the spinal cord, with the exception of segments caudal to S1, which were unlabeled. The distribution of ER-containing neurons to areas that are involved in processing of primary afferent nociceptive information suggests that the pain modulatory effects of estrogen may be exerted at the spinal level.
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| 5. |
- Hallbeck, Martin, et al.
(författare)
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Preprovasopressin mRNA is not present in dorsal root ganglia of the rat
- 1996
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Ingår i: Neuroscience Letters. - : Elsevier BV. - 0304-3940 .- 1872-7972. ; 209:10, s. 125-128
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Tidskriftsartikel (refereegranskat)abstract
- Immunohistochemical studies on colchic ine-treated rats have suggested that more than half of the neurons in dorsal root ganglia (DRG) contain vasopressin. Thus, vasopressin would be the most commonly found peptide in DRG neurons. In the present study we have reexamined the presence of vasopressin in DRG neurons, using a sensitive in situ hybridization method employing long riboprobes that will detect very small amounts of mRNA. The C3, C6, T2, T12, L2 and L5 DRG were studied. None of these ganglia contained any preprovasopressin mRNA. Yet, dense labeling for preprovasopressin mRNA was seen on simultaneously processed hypothalamic sections and a heavy preprotachykinin mRNA expression was seen in adjacent DRG sections. These findings demonstrate that vasopressin is not produced in DRG in normal rats.
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| 6. |
- Hermanson, Ola
(författare)
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Molecular mechanisms of nociception in the rat brain : anatomical connections and trans-synaptic regulation of gene expression of neurons in the pontine parabrachial nucleus
- 1997
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The pontine parabrachial nucleus (PB) is a major recipient of fibers fromnociceptive (pain-responsive) spinal and trigeminal dorsal horn neurons. With the use of combinations of molecular and morphological techniques, the anatomical connections of PB neurons and their expression of neuropeptide genes and transcription factors were studied, both in naive rats and in rats that had been subjected to nociceptive stimulation.A large number of neurons in PB expressed preproenkephalin mRNA(ppENK), which implies that these neurons synthesize the opioid enkephalin. One region of PB, the internal lateral subnucleus, contained many ppENKexpressing neurons that projected to the thalamic intralaminar nuclei, suggesting a role for these neurons in attentional mechanisms. Another region, the Kölliker-Fuse subnucleus (K-F), contained many ppENK-expressing neurons with descending projections to regions in the ventral medulla and spinal cord involved in pain control and autonomic modulation. The ppENKexpression in K-F increased after nociceptive stimulation of the neck or tail, suggesting that supraspinal opioidergic neurons with descending projections are activated by pain stimuli.Stimulation of the K-F region has been shown to elicit analgesia inanimals and humans. This analgesia has previously been ascribed to theactivation of noradrenergic neurons located in and close to K-F (the A7 cell group). Double-labeling procedures demonstrated that the ppENK-expressing neurons constituted a separate, much larger population, interspersed with the noradrenergic neurons. Thus, analgesia elicited by stimulation of K-F must involve the activation of opioidergic neurons.In search for the intracellular proteins that mediate the noxious-inducedup-regulation of ppENK, the expression of FOS in PB was studied after various types of nociceptive stimulation. FOS expression is low in PB of the naive animal, but FOS is rapidly produced after trans-synaptic activation, and it can bind to the DNA site that regulates ppENK transcription. However, noxiousevoked FOS was predominantly expressed in ppENK-negative neurons in PB. Another protein, CREB, can also regulate ppENK transcription. Therefore, the expression of active, phosphorylated, CREB was investigated in PB after nociceptive stimulation and was found to be present in the majority of theppENK-expressing neurons in K-F and the internal lateral subnucleus. These findings suggest that phosphorylation of CREB can mediate noxious-induced up-regulation of ppENK transcription in PB.Following nociceptive stimulation of the neck, tail, and hindlimb, most ofthe FOS was found in the dorsal and the superior lateral subnuclei of PB. The results suggest that neurons in these subnuclei are activated trans-synaptically by a direct spinal nociceptive input. The expression of FOS in PB after nociceptive stimulation of the face was found to be different from that seen after nociceptive stimulation of other parts of the body. Most of the FOSexpressing neurons were now detected in K-F, the external lateral, and the external medial subnuclei. This result is coherent with the termination pattern of fibers from the trigeminal dorsal horn, and suggests that neurons that are activated by nociceptive stimulation of the face have other functions than those activated by stimulation of other regions.Since FOS can bind to the ppCCK gene and regulate cholecystokininproduction, the parabrachial expression of preprocholecystokinin mRNA(ppCCK), which encodes the neuropeptide cholecystokinin, was investigated. Many ppCCK-expressing neurons were present in the superior lateral subnucleus, and these neurons displayed FOS after noxious stimulation. In addition, many ppCCK-expressing neurons in PBsl displayed the second messenger Ca2+/calmodulin-dependent kinase Il (CaMKII) and, after noxious stimulation, phosphorylated CREB. These findings point to a putative intracellular route for noxious-induced calcium-mediated regulation of ppCCK transcription through FOS induction via CaMKII and CREB. The ppCCKexpressing neurons in the superior lateral subnucleus were shown to project to the ventromedial hypothalamic nucleus, suggesting that they influence blood glucose homeostasis as a response to tissue damage.In search for a neuropeptide that is expressed by noxious-activated(FOS-1abeled) neurons in the dorsal lateral subnucleus, the preprodynorphin mRNA (ppDYN) expression was investigated. ppDYN encodes the opioid dynorphin, and the transcription of ppDYN can similar to other neuropeptide genes be regulated by the FOS protein. The dorsal lateral subnucleus was rich in ppDYN-expressing neurons, and many of the ppDYN-expressing neurons contained FOS, which implies that they are activated by nociceptive stimulation. The ppDYN-expressing neurons were found to project to the hypothalamic median preoptic nucleus, suggesting an involvel)lent of these neurons in cardiovascular regulation.In summary, the present study demonstrates that both opioidergic andnon-opioidergic neurons in a brainstem region, PB, are trans-synapticallyactivated by nociceptive stimulation in the awake rat. It is shown thatnociresponsive neurons in PB are organized in distinct cell groups that display different anatomical connections, intracellular signaling mechanisms, and gene expressions, suggesting different functions for these cell groups. It is suggested that nociresponsive parabrachial neurons influence the tuning and excitability of autonomic reflex circuits as part of an integrated response to tissue damage.
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| 7. |
- Håglin, Sofia, 1989-
(författare)
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Vitamin A regulated neuronal regeneration and homeostasis
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The olfactory epithelium is a dynamic tissue maintained by continuous neurogenesis throughout life. Upon injury, neurons and other olfactory cell types are regenerated through proliferation of horizontal stem cells. Some genes that regulate vitamin A metabolism are spatially expressed in the olfactory epithelium. Retinoic acid is a vitamin A derivate, a key regulator of proliferation and stem cell activity. Retinoic acid is generated and inactivated by enzymes with opposing expression patterns which create local variations in retinoic acid levels in the olfactory epithelium. The overall aim of this thesis is to elucidate functional relationships between retinoic acid metabolism and the regulation of temporal and spatial features of normal tissue homeostasis and regeneration of neurons within the olfactory epithelium.I have studied the association between the activity-dependent retinoic acid inactivating enzyme CYP26B1 and neurogenesis. During doubled stimulation by odorants and air flow the level of CYP26B1 was further induced in olfactory sensory neurons and proliferation of progenitor/stem cells was increased. In the absence of stimuli, CYP26B1 expression was reduced and proliferation decreased. Stimuli-independent transgenic over-expression of CYP26B1 resul-ted in increased proliferation, which was compared to acute intranasal admini-stration of retinoic acid that reduced the number of proliferating cells.The region of the olfactory epithelium with low CYP26B1 and high levels of retinoic acid synthesizing enzymes had the greatest level of proliferation and regenerated efficiently after chemical induced injury. Furthermore, neurons in this region differentiated surprisingly fast. In the region with high CYP26B1 and low levels of retinoic acid synthesizing enzymes the proliferation rate was low and the regeneration after injury was incomplete. Together these results indicate that retinoic acid within the olfactory epithelial stem cell niche regulates local differences in functional neuronal diversity, neurogenesis, and generative capacity of olfactory epithelial progenitor/stem cells.My research has revealed that ageing as well as constitutive transgenic over-expression of CYP26B1 activated dormant horizontal basal stem cells in the olfactory epithelium in an injury like manner. Continuous stem cell activation by constitutive CYP26B1 expression, repeated injuries or old age results in the appearance of epithelial patches devoid of normal olfactory epithelial cells, containing metaplastic respiratory cells. The respiratory patches either contained ciliated cells or a previously unidentified columnar secretory cell type. Moreover, we investigated whether increased proliferation of stem cells affected their regenerative potential over time. Repeated injury-repair cycles maximized the number of stem cell division, which decreased their potential to regenerate olfactory epithelial cells. Together these results indicate a premature exhaustion of the stem cell niche upon reduced levels of retinoic acid, repeated injury induced regeneration, and ageing.
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| 8. |
- Ilkhanizadeh, Shirin, et al.
(författare)
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Live Detection of Neural Progenitors and Glioblastoma Cells by an Oligothiophene Derivative
- 2023
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Ingår i: ACS Applied Bio Materials. - : American Chemical Society (ACS). - 2576-6422. ; 6:9, s. 3790-3797
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Tidskriftsartikel (refereegranskat)abstract
- There is an urgent need for simple and non-invasive identification of live neural stem/progenitor cells (NSPCs) in the developing and adult brain as well as in disease, such as in brain tumors, due to the potential clinical importance in prognosis, diagnosis, and treatment of diseases of the nervous system. Here, we report a luminescent conjugated oligothiophene (LCO), named p-HTMI, for non-invasive and non-amplified real-time detection of live human patient-derived glioblastoma (GBM) stem cell-like cells and NSPCs. While p-HTMI stained only a small fraction of other cell types investigated, the mere addition of p-HTMI to the cell culture resulted in efficient detection of NSPCs or GBM cells from rodents and humans within minutes. p-HTMI is functionalized with a methylated imidazole moiety resembling the side chain of histidine/histamine, and non-methylated analogues were not functional. Cell sorting experiments of human GBM cells demonstrated that p-HTMI labeled the same cell population as CD271, a proposed marker for stem cell-like cells and rapidly migrating cells in glioblastoma. Our results suggest that the LCO p-HTMI is a versatile tool for immediate and selective detection of neural and glioma stem and progenitor cells.
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| 9. |
- Jiang, Chonghe, 1951-, et al.
(författare)
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Cooling of the urinary bladder activates neurons in the dorsal horn of the spinal cord
- 2004
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Ingår i: NeuroReport. - : Ovid Technologies (Wolters Kluwer Health). - 0959-4965 .- 1473-558X. ; 15:2, s. 351-355
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Tidskriftsartikel (refereegranskat)abstract
- Although visceral innocuous cold receptors have been documented, the central termination of their afferents is unknown. We used menthol solution (0. 6 m M) to obtain selective activation of cold receptors in the urinary bladder of rats. Innocuous cold stimulation induced Fos expression in a population of neurons in the superficial dorsal horn of L6-SI segments of the spinal cord. Neurons in other regions of the spinal cord, e.g. the lumbar parasympathetic nucleus or the dorsal commissure region, were activated to a similar degree by menthol and control infusions, indicating a response to bladder filling. Our results are consistent with the proposal that subsets of modality-specific dorsal horn neurons convey specific information regarding the exteroceptive and interoceptive state of the animal. © 2004 Lippincott Williams & Wilkins.
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| 10. |
- Jungebluth, Philipp, et al.
(författare)
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Tracheobronchial transplantation with a stem-cell-seeded bioartificial nanocomposite : a proof-of-concept study
- 2011
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 378:9808, s. 1997-2004
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Tidskriftsartikel (refereegranskat)abstract
- Background Tracheal tumours can be surgically resected but most are an inoperable size at the time of diagnosis; therefore, new therapeutic options are needed. We report the clinical transplantation of the tracheobronchial airway with a stem-cell-seeded bioartificial nanocomposite. Methods A 36-year-old male patient, previously treated with debulking surgery and radiation therapy, presented with recurrent primary cancer of the distal trachea and main bronchi. After complete tumour resection, the airway was replaced with a tailored bioartificial nanocomposite previously seeded with autologous bone-marrow mononuclear cells via a bioreactor for 36 h. Postoperative granulocyte colony-stimulating factor filgrastim (10 mu g/kg) and epoetin beta (40 000 UI) were given over 14 days. We undertook flow cytometry, scanning electron microscopy, confocal microscopy epigenetics, multiplex, miRNA, and gene expression analyses. Findings We noted an extracellular matrix-like coating and proliferating cells including a CD105+ subpopulation in the scaffold after the reseeding and bioreactor process. There were no major complications, and the patient was asymptomatic and tumour free 5 months after trans plantation. The bioartificial nanocomposite has patent anastomoses, lined with a vascularised neomucosa, and was partly covered by nearly healthy epithelium. Post-operatively, we detected a mobilisation of peripheral cells displaying increased mesenchymal stromal cell phenotype, and upregulation of epoetin receptors, antiapoptotic genes, and miR-34 and miR-449 biomarkers. These findings, together with increased levels of regenerative-associated plasma factors, strongly suggest stem-cell homing and cell-mediated wound repair, extracellular matrix remodelling, and neovascularisation of the graft. Interpretation Tailor-made bioartificial scaffolds can be used to replace complex airway defects. The bioreactor reseeding process and pharmacological-induced site-specific and graft-specific regeneration and tissue protection are key factors for successful clinical outcome.
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