New research avenues derived from the gene expression analysis in the thermoregulatory region of the brain | Application
New research avenues derived from the gene expression analysis in the thermoregulatory region of the brain
Registration number: LIO-190171
Kliniskt forskningsprojekt för ST-läkare vid Landstinget i Östergötland
Application started by: Ana-Maria Vasilache, 2011-03-30
Professional title at the time of application: 1. ST-läkare 2. Doktorand
Work place at the time of application: 1. Klinisk Immunologi och Transfusionsmedicin, US, 2. IKE, Cellbiologi, HU
Last updated / corrected by: Ana-Maria Vasilache, 2013-03-11
Application received by: Region Östergötland
Granted and completedGranted and completed
Applicant: Ana-Maria Vasilache
Specialistläkare, Diagnostikcentrum

Information

Ansökan avser

Kliniskt forskningsprojekt för ST-läkare vid Landstinget i Östergötland

Ämnesområde

Nervsystemet

Sammanfattning av projektet

Aim:
1. To identify the Heat Shock Protein a1a/b (HSPa1a/b) gene and protein expressions in CNS in an acute animal model for inflammation.
2. Gene expression analysis of the blood-brain barrier cells: endothelial cell and perivascular cells
Background: Peripheral inflammatory processes elicit a number of central nervous system mediated sickness responses, including fever, fatigue, anorexia, hyperalgesia, social avoidance, and increased stress hormone release. While these reactions are adaptive during acute disease, they are detrimental for the affected individual during chronic disease conditions. There is also evidence that peripheral inflammation plays a role in the pathogenesis of several neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, and ALS (Letiembre, Liu et al. 2009), as well as in certain psychiatric conditions (Goldstein, Kemp et al. 2009), and that early-life exposure to inflammation may result in persistent maladaptive hypothalamic-pituitary-adrenal axis activation that may predispose individuals to various stress-related pathologies (Shanks, Larocque et al. 1995). Clarifying the cellular and molecular mechanisms of immune-to-brain signaling thus has implications not only for our understanding of the central processes involved in responding to acute illness but also for identifying targets for intervention in neurological and psychiatric disease.
It has been shown that many of the centrally elicited sickness responses are dependent on the central production of prostaglandin E2 (PGE2) in the blood-brain barrier (Engblom, Ek et al. 2002). Fever, the hallmark of peripheral inflammation, is mediated by the binding of PGE2 to its
EP3 receptor in the median preoptic area of the hypothalamus (later named only preoptic area) (Engblom, Saha et al. 2003). We recently demonstrated the EP3 receptor in this region of mouse brain and we developed a technique to selectively extract the preoptic area. Using that method we characterized the distribution of the EP3 isoforms in different conditions (Vasilache, Andersson et al. 2007).

As a next step we identified genes in the preoptic area that responded to PGE2 signaling. For this purpose, we ran a whole genome expression analysis on tissue from the preoptic area in mice that were immune challenge and they either could or could not (because of deletion of the gene synthesizing PGE2) produce PGE2 and display a febrile response. Genes that displayed differences between the two genotypes were validated with quantitative PCR. Of interest were in particular Heat shock proteins, which recently have received increased attention as they are believed to give protection in some neurodegenerative diseases as ALS and Alzheimer’s (Brown 2007). The two heat shock proteins, we identified as differentially expressed were HSPa1a/b. They are inducible chaperons and belong to the HSP70 family that are involved in protective mechanisms during stressful conditions both in the nervous system as well as in the other tissues (Hageman, van Waarde et al.). HSPa1a/b also have been shown to be associated with the regulation of the inflammatory response (Dokladny, Lobb et al. ; Sonna, Hawkins et al. 2010)

Project 1: The planned studies aim at further examining the brain gene and protein expressions of the HSPa1a/b during peripheral inflammation. Our finding demonstrates an up-regulation of the HSPa1a/b in animals that display PGE2 synthesis, and fever, in response to peripheral inflammation, and we now want to examine if the increased HSP expression is a consequence of PGE2 signaling or to the hyperthermia itself. Therefore, we will subject mice of both genotypes (i.e. those that can and cannot produce PGE2 respectively) to emotional stress, which in both genotypes give rise to a pronounced PGE2-independent hyperthermia, and then examine the gene expression profiles for HSPa1a/b in various brain regions. This project is planned to be completed by mid-2011.

Project 2: The microarray studies we have performed have been from microdissected tissue in discrete brain regions, such as the preoptic area. While this approach yields cells from discrete brain areas, it never-the-less includes several different cell types, such as neurons, glial cells and brain vascular cells. In order to be able to examine gene expression changes that occur specifically in the cells that transmit the peripheral immune signal to the brain, i.e. the blood-brain barrier cells, we have in collaboration with Mikael Sigvardsson’s groups developed a novel technique for isolating these cells by flow cytometry. In a pilot performed so far demonstrate that this is feasible and very powerful technique for examining gene expression in the descrete cell types. By quantitiative PCR we could identify several inflammatory responsive genes that were differentially expressed by the different cell types. Some of these data are included a paper that have been submitted for publication)[Engström, L. et al.submitted manuscript]. A next step we will use a whole genome assay to get the full picture of the gene expression that occur in the blood-brain barrier upon peripheral immune challenge. This project is planed to be completed by mid-2012.

Importance: These studies will give new insights into how inflammatory signals are processed in the brain and they may identify new drug targets for the treatment of inflammatory conditions. New knowledge into the mechanisms of immune-to-brain signaling may also contribute to our understanding of the etiology and pathogenesis of several psychiatric and neurodegenerative diseases in which inflammatory processes play an important role.

Doktorandanmäld

checked Ja
not checked Nej

Halvtidskontroll

not checked Ja
checked Nej

Disputerad

not checked Ja
not checked Nej

Docent

not checked Ja
checked Nej

Medarbetare/handledare

Supervisor

Fredrik Elinder
Professor, Medicinska fakulteten
Camilla Nilsberth
ST-läkare, Medicinska och Geriatriska akutkliniken

Forskningsmeriter

Publikationslista är inlagd/uppdaterad i ansökningssystemets personkort

checked Ja
not checked Nej

Forskningsmeriter (beskriv här eventuella tidigare forskningserfarenheter samt relevanta utbildningsmoment, utmärkelser m m)

2005: Försöksdjurskunskap, Hälsouniversitetet i Linköping, 4,5hp
2008: Grundläggande Biostatistik, Hälsouniversitetet i Linköping, 5hp
2009: Cytokines and Chemokines in inflammation, HU Linköping, 3hp
2010: Immunological Techniques, HU Linköping, 5hp

Forskningstid

Forskningstid önskas för följande antal månader (1-3 månader kan sökas)

3

Tidplan för uttag av forskningstid

 ÅrMånadAktivitet
Forskningstid2012första månadenvalidering av microarray med qPCR(microarray planerad för 2011)
Forskningstid2012andra månadenandra möjliga analyser beroende på utfallet: ELISA, IHC, nya djurförsök
Forskningstid2012tredje månadenförsök + manuskript
Forskningstid   
Forskningstid   

Redovisning (senast 3 månader efter att forskningstiden har utnyttjats)

Datum för redovisning

2013-03-11

Redovisning av forskningsprojekt

Under de 10 veckor forskningstid som jag fick utnyttja under 2012 och början på 2013 (pga mammaledighet) har jag kunnat ta min halvtidskontroll, färdiggöra ett manuskript samtidigt som jag kom igång med 2 nya projekt som ingår i min avhandling.

Tack så mycket för den värdefulla forskningstid jag fick av studierektorskansliet!

Decision

Decision date: 2011-06-13


New research avenues derived from the gene expression analysis in the thermoregulatory region of the brain | Application, from Region Östergötland
http://researchweb.org/is/en/lio/ansokan/190171