&lt;b&gt;DISTRIBUTION OF RETINOIC ACID RECEPTOR β PROTEINS IN RAT BRAIN: UP-REGULATION BY RETINOIC &lt;/b&gt;&lt;b&gt;ACID &lt;/b&gt;

Yamagata, Takanori; Momoi, Takashi; Kumagai, Hiromichi; Nishikawa, Takafumi; Yamaguchi, Masayoshi; Momoi, Mariko Y.

doi:10.2220/biomedres.14.183

Cited by 14 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Yamagata et al (1993) ont etudie le transport jusqu'au cerveau d'AR injecte dans la cavite peritoneale. D'autres resultats, obtenus dans des conditions d'apports suffisants en vitamine A chez le rat, ont montre que 90 % de l'AR total du cerveau n'est pas synthetise localement mais provient du pool circulant dans le plasma (Kurlandsky et al, 1995).…”

Section: La Vitamine a Et Le Cerveau Adulteunclassified

Vitamine A et vieillissement cérébral

Pallet

Enderlin

2011

OCL

View full text Add to dashboard Cite

La vitamine A est une vitamine liposoluble qui presente des rôles importants dans differents tissus de l'organisme. Elle est impliquee dans la vision, dans le maintien de l'integrite des surfaces epitheliales, dans l'immunite, la reproduction ou encore dans la croissance et le developpement (Blomhoff et Blomhoff, 2006). En dehors de son rôle dans la vision, la vitamine A agit principalement par l'intermediaire de son metabolite l'acide retinoïque (AR) qui, en se liant a des recepteurs nucleaires, regule l'expression de genes dans les tissus cibles.Il est bien connu que les retinoïdes, et en particulier l'AR, jouent un rôle capital dans le developpement du systeme nerveux central, mais ce n'est que recemment que son action dans le cerveau adulte a retenu l'attention des scientifiques. Les donnees actuellement disponibles sur ce sujet suggerent qu'une regulation tres fine de l'expression des genes cibles de l'AR est fondamentale pour des fonctions cerebrales optimales, telles que la plasticite synaptique, l'apprentissage et la memoire. Plus recemment encore, des donnees provenant de plusieurs etudes mettent en evidence l'implication de la voie de signalisation des retinoïdes dans l'etiologie de la maladie d'Alzheimer (MA). Metabolisme et transport de la vitamine APour les mammiferes superieurs la vitamine A provient exclusivement de l'alimentation : soit sous forme de vitamine preformee (dans sa forme majoritaire il s'agit de retinol esterifie par des acides gras a longues chaînes comme le palmitate de retinyle par exemple) dans les produits animaux, ou bien sous forme de carotenoïdes provitaminiques tels que le b-carotene, a-carotene, b-cryptoxanthine, presents dans les aliments d'origine vegetale (figure 1). On recommande actuellement que 60 % de l'apport en vitamine A soit sous la forme de carotenoïdes (sources vegetales) et 40 % sous forme de retinol (sources animales) (Cordain et al., 2005). L'ester de retinol (RE) doitêtre hydrolyse avant d'être absorbe au niveau intestinal. L'efficacite d'absorption est meilleure pour la vitamine A preformee (80 a 90 %) que pour les carotenoïdes (50-60 %). Le carotene est converti en retinol au niveau de la muqueuse intestinale. Le retinol est ensuite esterifie dans les cellules de la muqueuse par la LRAT (Lecithin : retinol acyltransferase), le RE resultant de cette catalyse est incorpore dans les chylomicrons et absorbe via le systeme lymphatique (Harrison, 2005). Dans des conditions nutritionnelles normales, la plupart de la vitamine A de l'organisme est stockee dans le foie (essentiellement sous forme de retinyl ester : RE) pour une part dans les hepatocytes et pour la majorite sous forme de gouttelettes lipidiques dans les cellules etoilees du foie (encore appelees Abstract: To date, convergent data on the role of retinoic acid in the mature brain have established that this molecule, which acts as a hormone, helps to preserve cerebral plasticity by controlling dendritic spine density as well as hippocampal neurogenesis. Deterioration in cerebral plasticity seems to be ...

show abstract

Section: La Vitamine a Et Le Cerveau Adulteunclassified

Vitamine A et vieillissement cérébral

Pallet

Enderlin

2011

OCL

View full text Add to dashboard Cite

show abstract

“…More recently it has been shown that the adult brain synthetizes RA, suggesting that retinoids may play an important role in the adult central nervous system [10]. The brain exhibits a selective distribution of cellular retinoid‐binding proteins [11]and of nuclear receptors [12]. Among the RAR, RARβ is the main isoform expressed in the mature brain and this receptor is up‐regulated by RA.…”

Section: Introductionmentioning

confidence: 99%

Aging decreases the abundance of retinoic acid (RAR) and triiodothyronine (TR) nuclear receptor mRNA in rat brain: effect of the administration of retinoids

et al. 1997

View full text Add to dashboard Cite

Aging is accompanied by troubles resulting from changes in hormonal and nutritional status. Therefore, the abundance of mRNA coding for triiodothyronine (TR) and retinoic acid (RA) nuclear receptors was studied in the brain of young, adult and aged (2.5, 6 and 24 months, respectively) rats. In the brain of aged rats, there was a lower abundance of TR and RAR mRNA and a lower activity of tissue transglutaminase (tTG), an enzyme the gene of which is a target for retinoids. Administration of RA in these rats restored TR and RAR mRNA and the activity of tTG in the brain. The importance of these observations to the function of the aged brain is discussed.

show abstract

“…For this purpose, the relative expression of RAR~, RXR~/,/ and TRa/~ nuclear receptors, the main isoforms expressed in the mature brain (19,28,34), and of two target genes, neurogranin (RC3) and tissue transglutaminase (tTG) was evaluated in PTU mice injected with vehicle or RA or T3. Expression of the protein tTG is highly regulated by RAR and its activity is considered to be a good indicator of retinoid cellular action (6).…”

mentioning

confidence: 99%

Retinoic acid reverses the PTU related decrease in neurogranin level in mice brain

Enderlin

Vallortigara

Alfos

et al. 2004

J. Physiol. Biochem.

View full text Add to dashboard Cite

Recent data have shown that fine regulation of retinoid mediated gene expression is fundamentally important for optimal brain functioning in aged mice. Nevertheless, alteration of the thyroid hormone signalling pathway may be a limiting factor, which impedes retinoic acid (RA) from exerting its modulating effect. Mild hypothyroidism is often described in the elderly. Thus, in the present study, it was of interest to determine if RA exerts its neurological modulating effect in mild hypothyroidism. To obtain further insight into this question, mice were submitted to a low propylthiouracyl (PTU) drink (0.05%) in order to slightly reduce the serum level of triiodothyronine (T3). A quantitative evaluation of RA nuclear receptors (RAR, RXR), T3 nuclear receptor (TR) and of neurogranin (RC3, a RA target gene which codes for a protein considered as a good marker of synaptic plasticity) in PTU treated mice injected with vehicle or RA or T3 was carried out. The PTU-related decrease in expression of RAR, RXR and RC3 was restored following RA or T3 administration, as observed in aged mice. The amount of TR mRNA, which was not affected in PTU treated mice, was increased only after T3 treatment as observed in overt hypothyroidism. These results suggest that neurobiological alterations observed in aged mice are probably related to RA and T3 signalling pathway modifications associated, in part, with mild changes in thyroid function.

show abstract

<b>DISTRIBUTION OF RETINOIC ACID RECEPTOR β PROTEINS IN RAT BRAIN: UP-REGULATION BY RETINOIC </b><b>ACID </b>

Cited by 14 publications

References 0 publications

Vitamine A et vieillissement cérébral

Vitamine A et vieillissement cérébral

Aging decreases the abundance of retinoic acid (RAR) and triiodothyronine (TR) nuclear receptor mRNA in rat brain: effect of the administration of retinoids

Retinoic acid reverses the PTU related decrease in neurogranin level in mice brain

Contact Info

Product

Resources

About