O90 Régulation de la visfatin au sein des macrophages primaires par les récepteurs nucléaires PPAR (Peroxisome Proliferator-Activated Receptor) gamma et LXR (Liver X Receptors)

2010 ◽  
Vol 36 ◽  
pp. A24
Author(s):  
T.H. Mayi ◽  
C. Duhem ◽  
F. Pattou ◽  
B. Staels ◽  
G. Chinetti-Gbaguidi
Keyword(s):  
Peroxisome Proliferator ◽  
Liver X Receptors ◽  
Peroxisome Proliferator Activated Receptor ◽  
Récepteurs Nucléaires ◽  
X Receptors

scholarly journals Effect of LXR/RXR agonism on brain and CSF Aβ40 levels in rats

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 138 ◽  
Author(s):  
Songli Wang ◽  
Paul Wen ◽  
Stephen Wood
Keyword(s):  
Principal Component ◽  
Amyloid Plaques ◽  
Peroxisome Proliferator ◽  
Liver X Receptors ◽  
Peroxisome Proliferator Activated Receptor ◽  
Abnormal Accumulation ◽  
Csf Levels ◽  
X Receptors ◽  
The Brain ◽  
Receptor Family

Alzheimer's disease (AD) is characterized pathologically by the presence of amyloid plaques and neurofibrillary tangles.  The amyloid hypothesis contends that the abnormal accumulation of Aβ, the principal component of amyloid plaques, plays an essential role in initiating the disease.  Impaired clearance of soluble Aβ from the brain, a process facilitated by apolipoprotein E (APOE), is believed to be a contributing factor in plaque formation.  APOE expression is transcriptionally regulated through the action of a family of nuclear receptors including the peroxisome proliferator-activated receptor gamma and liver X receptors (LXRs) in coordination with retinoid X receptors (RXRs).  It has been previously reported that various agonists of this receptor family can influence brain Aβ levels in rodents.  In this study we investigated the effects of LXR/RXR agonism on brain and cerebrospinal fluid (CSF) levels of Aβ40 in naïve rats.  Treatment of rats for 3 days or 7 days with the LXR agonist, TO901317 or the RXR agonist, Bexarotene did not result in significant changes in brain or CSF Aβ40 levels.

scholarly journals Activated Liver X Receptors Stimulate Adipocyte Differentiation through Induction of Peroxisome Proliferator-Activated Receptor γ Expression

2004 ◽  
Vol 24 (8) ◽  
pp. 3430-3444 ◽  
Author(s):  
Jong Bae Seo ◽  
Hyang Mi Moon ◽  
Woo Sik Kim ◽  
Yun Sok Lee ◽  
Hyun Woo Jeong ◽  
...  
Keyword(s):  
Gene Expression ◽  
Target Gene ◽  
Adipocyte Differentiation ◽  
Specific Gene ◽  
Peroxisome Proliferator ◽  
Liver X Receptors ◽  
Gene Promoters ◽  
Peroxisome Proliferator Activated Receptor ◽  
Specific Gene Expression ◽  
X Receptors

ABSTRACT Liver X receptors (LXRs) are nuclear hormone receptors that regulate cholesterol and fatty acid metabolism in liver tissue and in macrophages. Although LXR activation enhances lipogenesis, it is not well understood whether LXRs are involved in adipocyte differentiation. Here, we show that LXR activation stimulated the execution of adipogenesis, as determined by lipid droplet accumulation and adipocyte-specific gene expression in vivo and in vitro. In adipocytes, LXR activation with T0901317 primarily enhanced the expression of lipogenic genes such as the ADD1/SREBP1c and FAS genes and substantially increased the expression of the adipocyte-specific genes encoding PPARγ (peroxisome proliferator-activated receptor γ) and aP2. Administration of the LXR agonist T0901317 to lean mice promoted the expression of most lipogenic and adipogenic genes in fat and liver tissues. It is of interest that the PPARγ gene is a novel target gene of LXR, since the PPARγ promoter contains the conserved binding site of LXR and was transactivated by the expression of LXRα. Moreover, activated LXRα exhibited an increase of DNA binding to its target gene promoters, such as ADD1/SREBP1c and PPARγ, which appeared to be closely associated with hyperacetylation of histone H3 in the promoter regions of those genes. Furthermore, the suppression of LXRα by small interfering RNA attenuated adipocyte differentiation. Taken together, these results suggest that LXR plays a role in the execution of adipocyte differentiation by regulation of lipogenesis and adipocyte-specific gene expression.

scholarly journals Effect of LXR/RXR agonism on brain and CSF Aβ40 levels in rats

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 138 ◽  
Author(s):  
Songli Wang ◽  
Paul Wen ◽  
Stephen Wood
Keyword(s):  
Principal Component ◽  
Amyloid Plaques ◽  
Peroxisome Proliferator ◽  
Liver X Receptors ◽  
Peroxisome Proliferator Activated Receptor ◽  
Abnormal Accumulation ◽  
Csf Levels ◽  
X Receptors ◽  
The Brain ◽  
Receptor Family

Alzheimer's disease (AD) is characterized pathologically by the presence of amyloid plaques and neurofibrillary tangles. The amyloid hypothesis contends that the abnormal accumulation of Aβ, the principal component of amyloid plaques, plays an essential role in initiating the disease. Impaired clearance of soluble Aβ from the brain, a process facilitated by apolipoprotein E (APOE), is believed to be a contributing factor in plaque formation. APOE expression is transcriptionally regulated through the action of a family of nuclear receptors including the peroxisome proliferator-activated receptor gamma and liver X receptors (LXRs) in coordination with retinoid X receptors (RXRs). It has been previously reported that various agonists of this receptor family can influence brain Aβ levels in rodents. In this study we investigated the effects of LXR/RXR agonism on brain and cerebrospinal fluid (CSF) levels of Aβ40 in naïve rats. Treatment of rats for 3 days or 7 days with the LXR agonist, T0901317 or the RXR agonist, bexarotene did not result in significant changes in brain or CSF Aβ40 levels.

Expression of peroxisomal proliferator-activated receptors and retinoid X receptors in the kidney

1999 ◽  
Vol 277 (6) ◽  
pp. F966-F973 ◽  
Author(s):  
Tianxin Yang ◽  
Daniel E. Michele ◽  
John Park ◽  
Ann M. Smart ◽  
Zhiwu Lin ◽  
...  
Keyword(s):  
Collecting Duct ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Retinoid X Receptors ◽  
Nephron Segments ◽  
Process Formation ◽  
Nephron Segment ◽  
Altered Cell ◽  
X Receptors ◽  
Almost All

The discovery that 15-deoxy-Δ12,14-prostaglandin J2(15d-PGJ2) is a ligand for the γ-isoform of peroxisome proliferator-activated receptor (PPAR) suggests nuclear signaling by prostaglandins. Studies were undertaken to determine the nephron localization of PPAR isoforms and their heterodimer partners, retinoid X receptors (RXR), and to evaluate the function of this system in the kidney. PPARα mRNA, determined by RT-PCR, was found predominately in cortex and further localized to proximal convoluted tubule (PCT); PPARγ was abundant in renal inner medulla, localized to inner medullary collecting duct (IMCD) and renal medullary interstitial cells (RMIC); PPARβ, the ubiquitous form of PPAR, was abundant in all nephron segments examined. RXRα was localized to PCT and IMCD, whereas RXRβ was expressed in almost all nephron segments examined. mRNA expression of acyl-CoA synthase (ACS), a known PPAR target gene, was stimulated in renal cortex of rats fed with fenofibrate, but the expression was not significantly altered in either cortex or inner medulla of rats fed with troglitazone. In cultured RMIC cells, both troglitazone and 15d-PGJ2 significantly inhibited cell proliferation and dramatically altered cell shape by induction of cell process formation. We conclude that PPAR and RXR isoforms are expressed in a nephron segment-specific manner, suggesting distinct functions, with PPARα being involved in energy metabolism through regulating ACS in PCT and with PPARγ being involved in modulating RMIC growth and differentiation.

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