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Wang H, Tan Z, Zheng Q, Yu J. Metabolic Brain Network Analysis of Hypothyroidism Symptom Based on [18F]FDG-PET of Rats. Mol Imaging Biol 2018. [DOI: 10.1007/s11307-018-1182-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Yu J, Tang YY, Feng HB, Cheng XX. A behavioral and micro positron emission tomography imaging study in a rat model of hypothyroidism. Behav Brain Res 2014; 271:228-33. [DOI: 10.1016/j.bbr.2014.06.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 06/05/2014] [Accepted: 06/09/2014] [Indexed: 11/28/2022]
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3
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Féart C, Mingaud F, Enderlin V, Husson M, Alfos S, Higueret P, Pallet V. Differential effect of retinoic acid and triiodothyronine on the age-related hypo-expression of neurogranin in rat. Neurobiol Aging 2005; 26:729-38. [PMID: 15708448 DOI: 10.1016/j.neurobiolaging.2004.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 06/10/2004] [Accepted: 06/21/2004] [Indexed: 12/20/2022]
Abstract
Given the important role of retinoids and thyroid hormone for optimal brain functioning and the tenuous relationship between retinoic acid (RA) and triiodothyronine (T3) signalings, we compared the effects of RA or T3 administrations on RA and T3 nuclear receptors (RAR, RXR and TR) and on their target genes, neuromodulin (GAP43) and neurogranin (RC3) in 24-month-old rats. Quantitative real time PCR and western blot analysis allowed us to verify that retinoid and thyroid signalings and GAP43 and RC3 expression are affected by age. By in situ hybridization we observed a decreased expression of RC3 in hippocampus, striatum and cerebral cortex. RARbeta, RXRbeta/gamma and GAP43 were up-regulated by RA as well as T3 treatment. The abundance of TRalpha/beta mRNA and RC3 expression were only increased by T3 administration in the whole brain. This up-regulator effect of T3 on RC3 was only observed in the striatum. During aging, T3 become a limiting factor alone able to correct the age-related concomitant hypo-activation of retinoid and thyroid signalings and alterations of synaptic plasticity.
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Affiliation(s)
- C Féart
- Unité de Nutrition et Signalisation Cellulaire (E.A. MENRT; USC INRA) ISTAB, Avenue des Facultés, Université Bordeaux I, 33405 Talence cedex, France
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4
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Enderlin V, Vallortigara J, Alfos S, Féart C, Pallet V, Higueret P. Retinoic acid reverses the PTU related decrease in neurogranin level in mice brain. J Physiol Biochem 2004; 60:191-8. [PMID: 15700765 DOI: 10.1007/bf03167028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
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.
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Affiliation(s)
- V Enderlin
- Unité de Nutrition et Signalisation Cellulaire (E.A. MENRT; USC INRA) ISTAB, Université Bordeaux 1, Avenue des Facultés, 33405 Talence cedex, France.
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5
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Haberkorn V, Oziol L, Goudonnet H. 9-cis-Retinoic acid regulation of four UGT isoforms in hepatocytes from rats with various thyroid states. Pharm Res 2004; 20:1568-73. [PMID: 14620509 DOI: 10.1023/a:1026174931690] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To investigate the influence of thyroid hormone status on the regulation of UGTs expression by 9-cis-retinoic acid in cultured rat primary hepatocytes. METHODS Hepatocytes from rats with various thyroid states were isolated and treated with 9-cis retinoic acid (1 x 10(-6) M). mRNA was amplified by reverse transcription and polymerase chain reaction (RT-PCR) and quantified by UV light densitometry. Variations in the expression levels of four different UGT isoforms (UGT1A1, 1A2, 1A5, and 1A6) that are involved in the glucuronication of bilirubin and phenols were determined by comparison with those of an internal standard, beta-actin, which is known to be insensitive to nutritional and hormonal conditions. RESULTS Primary hepatocyte cultures from rats with various thyroid states present similar metabolite characteristics to those from hypo- or hyperthyroid animals. The treatment of hepatocytes from hypothyroid rats with 9-cis-retinoic acid (1 x 10(-6) M) did not significantly modify bilirubin and phenol-UGT isoform expression. In contrast, in hepatocytes from normal and specially hyperthyroid rats treated with 9-cis-retinoic acid, UGT mRNA levels were modified. This suggests that the effect of retinoic acid on UGT mRNA expression requires the presence of thyroid hormone. This was confirmed by the treatment of cultured hepatocytes from hypothyroid rats with both retinoic acid and L-T3. CONCLUSIONS This study demonstrates that in cultured hepatocytes, the thyroid status can differentially modulate the expression of four UGT isoforms, and the regulation of their expression can be affected by 9-cis-retinoic acid.
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Affiliation(s)
- Valérie Haberkorn
- Unité de Biochimie-Pharmacologie-Toxicologie, EA/MENRT 2980, UFR Pharmacie, 7 bd Jeanne d'Arc, BP 87900, 21 079 Dijon-Cedex, France.
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Haberkorn V, Heydel JM, Mounie J, Artur Y, Goudonnet H. Vitamin A modulates the effects of thyroid hormone on UDP-glucuronosyltransferase expression and activity in rat liver. Mol Cell Endocrinol 2002; 190:167-75. [PMID: 11997190 DOI: 10.1016/s0303-7207(01)00681-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
We studied the influence of thyroid hormones and vitamin A status on the regulation of UDP-glucuronosyltransferase (UGT) expression and the glucuronidation of thyroid hormones by UGTs. For this, we used an original model of rats fed with different vitamin A diets and implanted subcutaneously by osmotic minipumps delivering vehicle or thyroid hormones, which permitted the control of plasma thyroid hormone concentrations. The activity and expression of family 1 UGTs are correlated and were significantly modified by both thyroid status and amounts of retinol in the diet. Dietary vitamin A did not perturbe the UGT1A expression in thyroidectomized animals. Thyroid hormones and dietary vitamin A did not affect the activity and expression of family 2 UGTs. We conclude that thyroid hormones and vitamin A are co-regulator of the UGT1 family expression, without affecting the UGT2 family; by modifying activity and expression of the bilirubin UOT isoform, a member of UGT1 family, thyroid hormone reduced the glucuronidation of T4 and rT3.
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Affiliation(s)
- Valérie Haberkorn
- Unité de Biochimie-Pharmacologie-Toxicologie, EA/MENRT 2980 UFR Pharmacie, Université de Bourgogne, 7 Bd. Jeanne d'Arc, BP 87900, 21079 Dijon, France.
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7
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Bonilla S, Redonnet A, Noël-Suberville C, Groubet R, Pallet V, Higueret P. Effect of a pharmacological activation of PPAR on the expression of RAR and TR in rat liver. J Physiol Biochem 2001. [DOI: 10.1007/bf03179807] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Dauncey MJ, White P, Burton KA, Katsumata M. Nutrition-hormone receptor-gene interactions: implications for development and disease. Proc Nutr Soc 2001; 60:63-72. [PMID: 11310425 DOI: 10.1079/pns200071] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nutrition profoundly alters the phenotypic expression of a given genotype, particularly during fetal and postnatal development. Many hormones act as nutritional signals and their receptors play a key role in mediating the effects of nutrition on numerous genes involved in differentiation, growth and metabolism. Polypeptide hormones act on membrane-bound receptors to trigger gene transcription via complex intracellular signalling pathways. By contrast, nuclear receptors for lipid-soluble molecules such as glucocorticoids (GC) and thyroid hormones (TH) directly regulate transcription via DNA binding and chromatin remodelling. Nuclear hormone receptors are members of a large superfamily of transcriptional regulators with the ability to activate or repress many genes involved in development and disease. Nutrition influences not only hormone synthesis and metabolism but also hormone receptors, and regulation is mediated either by specific nutrients or by energy status. Recent studies on the role of early environment on development have implicated GC and their receptors in the programming of adult disease. Intrauterine growth restriction and postnatal undernutrition also induce striking differences in TH-receptor isoforms in functionally-distinct muscles, with critical implications for gene transcription of myosin isoforms. glucose transporters, uncoupling proteins and cation pumps. Such findings highlight a mechanism by which nutritional status can influence normal development, and modify nutrient utilization. thermogenesis. peripheral sensitivity to insulin and optimal cardiac function. Diet and stage of development will also influence the transcriptional activity of drugs acting as ligands for nuclear receptors. Potential interactions between nuclear receptors, including those for retinoic acid and vitamin D, should not be overlooked in intervention programmes using I or vitamin A supplementation of young and adult human populations
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Affiliation(s)
- M J Dauncey
- Developmental Genetics Programme, The Babraham Institute, Cambridge, UK.
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Bonilla S, Redonnet A, Noël-Suberville C, Pallet V, Garcin H, Higueret P. High-fat diets affect the expression of nuclear retinoic acid receptor in rat liver. Br J Nutr 2000; 83:665-71. [PMID: 10911775 DOI: 10.1017/s0007114500000842] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The purpose of this study was to differentiate between the effects of the amount and the type of dietary lipids on the expression of the retinoic acid receptor (RAR), but also the peroxisome proliferator-activated receptor (PPAR) and the receptor of the 9-cis retinoic acid (retinoid X receptor (RXR)) in rat liver. Six groups of eight rats (5-weeks old) were fed during 4 weeks on the following diets: control 50 g vegetable oil/kg, high-fat diet 250 g vegetable oil/kg. These oils were either coconut oil (rich in saturated fatty acids) or olive oil (rich in monounsaturated fatty acids) or safflower oil (rich in polyunsaturated fatty acids, mainly as n-6). The three high-fat diets induced a significant decrease of the maximal binding capacity of RAR and of the abundance of RAR beta mRNA. Simultaneously, an increased expression of PPAR alpha mRNA was observed while no significant difference on abundance of RXR alpha mRNA was observed. The mechanisms involved are probably multiple, but one hypothesis is that a modification of the equilibrium between the nuclear receptors, resulting from an increased expression of PPAR, induces a decreased expression of RAR in rat liver.
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Affiliation(s)
- S Bonilla
- Laboratoire de Nutrition-ISTAB, Université Bordeaux I, Talence, France
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Abstract
In utero exposure to the anticonvulsant drug phenytoin has been shown to alter normal embryonic development, leading to a pattern of dysmorphogenesis known as the Fetal Hydantoin Syndrome. This embryopathy is characterized by growth retardation, microcephaly, mental deficiency, and craniofacial malformations, although the precise mechanism(s) by which phenytoin alters normal developmental pathways remains unknown. To better understand the molecular events involved in the pathogenesis of phenytoin-induced congenital defects, alterations in gene expression were examined during critical periods of craniofacial development. Pregnant SWV mice were administered phenytoin (60 mg/kg/day) from gestational day 6.5 until they were sacrificed at selected developmental time points. Tissue from the craniofacial region of control and exposed embryos was isolated, and samples were subjected to in situ transcription, antisense RNA amplification, and hybridization on reverse Northern blots to quantitatively assess expression of 36 candidate genes. Chronic phenytoin exposure significantly altered expression of several genes at distinct times during morphogenesis. Results of these studies show that expression of the retinoic acid receptors (RAR) alpha, beta, and gamma were significantly increased by phenytoin exposure. Elevations in gene expression of laminin beta 1, and the growth factors IGF-2, TGF alpha, and TGF beta 1, were also demonstrated in the craniofacial region of phenytoin-exposed embryos. As several of these genes are transcriptionally regulated by retinoic-acid-responsive elements in their promoter regions, phenytoin-induced alterations in expression of the RAR isoforms may have severe downstream consequences in the regulation of events necessary for normal craniofacial development. Such alterations occurring coordinately at critical times during craniofacial development may account for the dysmorphogenesis often associated with phenytoin exposure.
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Affiliation(s)
- J Gelineau-van Waes
- Department of Veterinary Anatomy and Public Health, Texas A&M University, College Station 77843-4458, USA
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Bonilla S, Noël-Suberville C, Puy-Portillo M, Simon E, Del Barrio A, Garcin H, Higueret P. A diet rich in coconut oil decreases the expression of retinoic acid and triiodothyronine nuclear receptors in rat liver. Nutr Res 1998. [DOI: 10.1016/s0271-5317(98)00133-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Noel-Suberville C, Pallet V, Audouin-Chevallier I, Higueret P, Bonilla S, Martinez AJ, Zulet MA, Portillo MP, Garcin H. Expression of retinoic acid, triiodothyronine, and glucocorticoid hormone nuclear receptors is decreased in the liver of rats fed a hypercholesterolemia-inducing diet. Metabolism 1998; 47:301-8. [PMID: 9500567 DOI: 10.1016/s0026-0495(98)90261-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Several studies have shown that dietary factors modulate cell signaling pathways. The aim of this study was to determine whether a hypercholesterolemia-inducing diet rich in saturated fat and cholesterol modifies rat liver expression of the nuclear receptors of retinoic acid (RAR), triiodothyronine (TR), and glucocorticoid hormone (GR), which are transcriptional factors. The experimental diet contained coconut oil 25 g/100 g as a source of lipids, cholesterol 1 g/100 g, and cholic acid 0.5 g/100 g, and the control diet contained olive oil 5 g/100 g. After 26 days of feeding the hypercholesterolemia-inducing diet, a lower binding capacity of the nuclear receptors and a smaller amount of their mRNA were observed. Moreover, the activities of malic enzyme (ME) and tyrosine aminotransferase (TAT), whose gene promotors contain a response element to TR and GR, respectively, were significantly decreased. These changes occurred in a cellular environment characterized by a high level of cholesterol and free fatty acids (FFAs). Thus, two nonexclusive hypotheses can be proposed to explain this decreased expression of nuclear receptors, one emphasizing the effect of lipidic components on the cellular amount of receptor ligands (retinoic acid [RA] and triiodothyronine [T3]), the other emphasizing a modification of the balance between nuclear receptors that could impede the upregulation of TR and RAR.
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Pallet V, Azaïs-Braesco V, Enderlin V, Grolier P, Noël-Suberville C, Garcin H, Higueret P. Aging decreases retinoic acid and triiodothyronine nuclear expression in rat liver: exogenous retinol and retinoic acid differentially modulate this decreased expression. Mech Ageing Dev 1997; 99:123-36. [PMID: 9483487 DOI: 10.1016/s0047-6374(97)00098-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The expression of nuclear receptors of retinoic acid (RAR) and triiodothyronine (TR) was analyzed in the liver of rats aged 2.5 (young), 6 (adult) and 24 (aged) months. In aged rats, decreased binding properties, binding capacity (Cmax) and affinity (Ka), of nuclear receptors were observed. This resulted, at least in part, from decreased transcription of receptor genes in that the amount of their mRNA also decreased. Moreover, the activity of malic enzyme (ME) and tissue transglutaminase (tTG), whose genes are TR and RAR responsive, respectively, was reduced in aged rats. These results are in agreement with the decreased binding capacity of these receptors. An inducer-related increase of RAR and TR expression was observed 24 h after a single dose of retinoic acid administration (5 mg/kg), while retinol administration (retinyl palmitate, 13 mg/kg) was without incidence on nuclear receptor expression in aged rats.
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Affiliation(s)
- V Pallet
- Laboratoire de Nutrition, ISTAB, Université de Bordeaux I, Talence, France
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Hanley K, Devaskar UP, Hicks SJ, Jiang Y, Crumrine D, Elias PM, Williams ML, Feingold KR. Hypothyroidism delays fetal stratum corneum development in mice. Pediatr Res 1997; 42:610-4. [PMID: 9357932 DOI: 10.1203/00006450-199711000-00010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The epidermal permeability barrier, required for terrestrial life, is localized to lipid-enriched lamellar membranes in the extracellular spaces of the stratum corneum (SC). Immaturity of the SC is a significant contributor to morbidity and mortality in premature infants. Previous studies have shown that supraphysiologic concentrations of thyroid hormone accelerate epidermis/SC ontogenesis. Here we studied SC development in Hyt/Hyt mice who are genetically hypothyroid due to a mutation in the TSH receptor. In control mice on d 18 of gestation (term 19.5 d), only focal areas displayed a mature SC membrane pattern. By 19 d of gestation there was a mature multilayered SC with lamellar unit structures filling the extracellular spaces similar to that seen in mature mice. In Hyt/Hyt mice SC development was delayed at both 18 and 19 d of gestation. In both strains of mice, within the first day after birth there were no differences in epidermal or SC appearance, and the SC was fully mature. These findings indicate that thyroid hormone plays a physiologic role during normal intrauterine development of the SC. However, normal SC maturation ultimately occurs, indicating that thyroid hormone is not absolutely essential. Previous studies have shown that glucocorticoids accelerate SC development in euthyroid rats, and in the present study we demonstrate that glucocorticoids also accelerate SC ontogenesis in euthyroid mice. In contrast, in Hyt/Hyt mice glucocorticoids did not accelerate or normalize SC development, indicating that the glucocorticoid effect on SC maturation requires a euthyroid state or that glucocorticoids act via thyroid hormone. These studies demonstrate that thyroid hormone status is an important regulator of fetal SC development.
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Affiliation(s)
- K Hanley
- Department of Medicine and Dermatology, University of California, San Francisco 94121, USA
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Enderlin V, Alfos S, Pallet V, Garcin H, Azaïs-Braesco V, Jaffard R, Higueret P. Aging decreases the abundance of retinoic acid (RAR) and triiodothyronine (TR) nuclear receptor mRNA in rat brain: effect of the administration of retinoids. FEBS Lett 1997; 412:629-32. [PMID: 9276480 DOI: 10.1016/s0014-5793(97)00845-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
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.
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MESH Headings
- Age Factors
- Aging/drug effects
- Aging/metabolism
- Animals
- Brain/drug effects
- Brain/metabolism
- Diterpenes
- Intubation, Gastrointestinal
- Male
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- RNA, Messenger/physiology
- Rats
- Rats, Wistar
- Receptors, Retinoic Acid/drug effects
- Receptors, Retinoic Acid/metabolism
- Receptors, Retinoic Acid/physiology
- Receptors, Thyroid Hormone/drug effects
- Receptors, Thyroid Hormone/metabolism
- Receptors, Thyroid Hormone/physiology
- Retinyl Esters
- Tretinoin/administration & dosage
- Vitamin A/administration & dosage
- Vitamin A/analogs & derivatives
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Affiliation(s)
- V Enderlin
- Laboratoire de Nutrition, ISTAB, Université Bordeaux I, Talence, France
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Enderlin V, Pallet V, Alfos S, Dargelos E, Jaffard R, Garcin H, Higueret P. Age-related decreases in mRNA for brain nuclear receptors and target genes are reversed by retinoic acid treatment. Neurosci Lett 1997; 229:125-9. [PMID: 9223607 DOI: 10.1016/s0304-3940(97)00424-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ageing is accompanied by certain problems resulting from changes of hormonal status, in particular thyroid hormone (T3) status and vitamin A status. Since retinoic acid (RA), the active metabolite of vitamin A, and T3 play physiological roles in the adult brain, the effect of ageing on the amounts of mRNA for retinoic acid (RAR and RXR) and triiodothyronine (TR) nuclear receptors were studied. Also, the expression of RA and T3 target genes, tissue transglutaminase (tTG) and neurogranin (RC3), was measured in the whole brain and in the hippocampus of mice. Relative to young (3 months) mice, aged (22 months) mice exhibited lower amounts of RAR, RXR and TR mRNA concomitantly with a lower expression of tTG and RC3. RA administration to old mice (24 h before sacrifice) was able to restore the amount of mRNA of nuclear receptors and of RC3. It is hypothesized that a decrease in the cellular action of RA and T3 could play a role, via a decrease in the expression of RC3, in the alteration of synaptic plasticity occurring in aged mice.
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Affiliation(s)
- V Enderlin
- Laboratoire de Nutrition, Université Bordeaux I, Talence, France
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