Download presentation
Presentation is loading. Please wait.
Published byDwayne Mitchell Modified over 9 years ago
1
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html
2
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html
3
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html
4
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html Glucose displaces a labelled high-affinity LXR ligand a, d-Glucose and glucose-6-phosphate compete for LXR binding and displace [ 3 H]T0901317 (25 nM) in an SPA assay. b, [ 3 H]Glucose binds LXR. A scatchard analysis is shown in the inset. Labelled glucose did not bind the RXR LBD (data not shown). Unlabelled LXR ligands displace bound [ 3 H]glucose (20 mM) but not completely. Values are expressed as percentage binding of labelled compound. Fractional occupancy of the receptor (see Methods) is 95% for LXR- and 98% for LXR-. c.p.m., counts per minute. c, Addition of labelled glucose to a saturating dose of [ 3 H]T0901317 (10 µ M) increases scintillation in an SPA assay; percentage efficacy is relative to 10 µ M [ 3 H]T091317. d, Addition of glucose, but not GW3965, to a maximal dose of T0901317 enhances coactivator recruitment. Note the different scales. Values are presented as fold induction versus vehicle (increase in coactivator recruitment measured as a change in 665/615 nm emission relative to vehicle). All error bars indicate s.d.; experiments performed in triplicate.
5
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html Glucose regulates direct LXR target genes in vivo (a) HepG2 cells cultured in 0 mM (white bars), 2 mM (grey bars) or 25 mM (black bars) glucose medium were treated overnight with GW3965 (1 µ M), 22-( R )-hydroxycholesterol (5 µ M), or D-glucose (20 mM) and gene expression was analysed using qRT-PCR. Glucose stimulates expression of direct LXR cholesterol homeostasis target genes. Note that efficacy of known LXR ligands increases with increasing glucose concentration. All error bars represent s.d.
6
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html Glucose regulates direct LXR target genes in vivo (b) Glucose induces LXR target genes in mouse liver. Mice fasted overnight were challenged orally with GW3965 (50 mg ハ kg -1 ), or re-fed with a glucose or sucrose diet and killed 6 h later. d-Glucose and GW3965 regulate the same direct LXR targets (genes involved in cholesterol and fatty acid metabolism) as well as indirect carbohydrate metabolism targets. All error bars represent s.d., n = 5-6 mice per group. Asterisk, P <0.05; double asterisk, P <0.001 treatment versus fasted.
7
N. Mitro et al. Nature advance online publication 24 December 2006 doi:10.1038/nature05449 http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature05449.html Schematic representation of pathways influencing glucose fate in the liver Glucose induces insulin secretion, suppressing hepatic gluconeogenesis and – through LXR – activating SREBP-1c expression and lipogenesis. Glucose can also bind directly to LXR to induce SREBP-1c expression, suppress hepatic glucose output, and increase ChREBP expression. ChREBP activitity is modulated by glucose metabolites, further increasing lipogenesis. For clarity, glycogen metabolism is not included in the diagram.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.