295. Peroxisome proliferator activated receptor-alpha is involved in H+-monocarboxylate transporter 2 and catalase protein expression in cultured preimplantation mouse embryos

2005 ◽  
Vol 17 (9) ◽  
pp. 125
Author(s):  
S. Jansen ◽  
M. Pantaleon ◽  
P. L. Kaye
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Mouse Embryos ◽  
Preimplantation Development ◽  
Monocarboxylate Transporter ◽  
Metabolic Inhibitors ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Beta Oxidation ◽  
Peroxisome Proliferator Activated Receptor

Cleavage stage embryos consume pyruvate before switching to glucose as the major energy substrate for blastocyst formation. This switch is conditional, because freshly collected two-cell embryos form blastocysts without glucose by increasing pyruvate consumption. Zygotes cultured without glucose cannot adapt in this way and degenerate, but paradoxically demonstrate upregulation of the H+-monocarboxylate transporter protein, MCT2, in morulae. MCT2 is a high affinity transporter implicated in redox shuttling for peroxisomal beta-oxidation of fatty acids.3 Fatty acids may provide energy for embryos2 but peroxisomal beta-oxidation has not been explored in preimplantation development. Rat oocytes possess a primitive peroxisomal system.1 The possibility therefore exists that MCT2 may also be linked to fatty acid metabolism in embryos. Peroxisome proliferator activated receptor (PPAR)-alpha is a transcriptional regulator of fatty acid transport and beta-oxidation, and controls expression of catalase, a major peroxisomal enzyme. This investigation explores the role of PPAR-α in the glucose-driven control of MCT2 expression in mouse embryos. Zygotes (18 h post-hCG) were cultured in KSOM in the presence or absence of glucose, or KSOM with selective agonists of PPAR-α, fenofibrate and WY 14643. Expression of MCT2 and catalase was analysed by confocal laser scanning immunohistochemistry and western blot. Results confirm the presence of catalase throughout preimplantation development. With glucose, cytoplasmic immunoreactivity for catalase was punctate and diffuse, while MCT2 was localised to apical membranes of outer blastomeres in morulae. Without glucose, catalase and MCT2 expression were increased with notable localisation of catalase to nuclei. This response was reflected in morulae cultured in the presence of glucose and PPAR-α agonists. These data suggest that PPAR-α plays a role in controlling catalase and MCT2 expression in embryos, and that conditions in the absence of glucose are more conducive for PPAR-α activation. (1)Figueroa C, Kawada ME, Veliz LP, Hidalgo U, Barros C, Gonzalez S and Santos MJ (2000) Peroxisomal proteins in rat gametes. Cell Biochem Biophys 32, 259–268.(2)Hewitson LC, Martin KL and Leese HJ (1996) Effects of metabolic inhibitors on mouse preimplantation embryo development and the energy metabolism of isolated inner cell masses. Mol Reprod Dev 43, 323–330.(3)McClelland GB, Khanna S, Gonzalez GF, Butz CE and Brooks GA (2003) Peroxisomal membrane monocarboxylate transporters: evidence for a redox shuttle system? Biochem Biophys Res Commun 304, 130–135.

scholarly journals Role of peroxisome proliferator-activated receptor-α on the synthesis of monounsaturated fatty acids in goat mammary epithelial cells

2020 ◽  
Vol 98 (3) ◽  
Author(s):  
Huibin Tian ◽  
Jun Luo ◽  
Hengbo Shi ◽  
Xiaoying Chen ◽  
Jiao Wu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Mammary Epithelial Cells ◽  
Acid Synthesis ◽  
Mammary Epithelial ◽  
Mrna Abundance ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Goat Mammary Epithelial Cells

Abstract A key member of the nuclear receptor superfamily is the peroxisome proliferator-activated receptor alpha (PPARA) isoform, which in nonruminants is closely associated with fatty acid oxidation. Whether PPARA plays a role in milk fatty acid synthesis in ruminants is unknown. The main objective of the present study was to use primary goat mammary epithelial cells (GMEC) to activate PPARA via the agonist WY-14643 (WY) or to silence it via transfection of small-interfering RNA (siRNA). Three copies of the peroxisome proliferator-activated receptor response element (PPRE) contained in a luciferase reporter vector were transfected into GMEC followed by incubation with WY at 0, 10, 20, 30, 50, or 100 µM. A dose of 50 µM WY was most effective at activating PPRE without influencing PPARA mRNA abundance. Transfecting siRNA targeting PPARA decreased its mRNA abundance to 20% and protein level to 50% of basal levels. Use of WY upregulated FASN, SCD1, ACSL1, DGAT1, FABP4, and CD36 (1.1-, 1.5-, 2-, 1.4-, 1.5-, and 5-fold, respectively), but downregulated DGAT2 and PGC1A (−20% and −40%, respectively) abundance. In contrast, triacylglycerol concentration decreased and the content and desaturation index of C16:1 and C18:1 increased. Thus, activation of PPARA via WY appeared to channel fatty acids away from esterification. Knockdown of PPARA via siRNA downregulated ACACA, SCD1, AGPAT6, CD36, HSL, and SREBF1 (−43%, −67%, −16%, −56%, −26%, and −29%, respectively), but upregulated ACSL1, DGAT2, FABP3, and PGC1A (2-, 1.4-, 1.3-, and 2.5-fold, respectively) mRNA abundance. A decrease in the content and desaturation index of C16:1 and C18:1 coupled with an increase in triacylglycerol content accompanied those effects at the mRNA level. Overall, data suggest that PPARA could promote the synthesis of MUFA in GMEC through its effects on mRNA abundance of genes related to fatty acid synthesis, oxidation, transport, and triacylglycerol synthesis.

scholarly journals Peroxisome-proliferator-activated receptor-α (PPARα) deficiency leads to dysregulation of hepatic lipid and carbohydrate metabolism by fatty acids and insulin

2002 ◽  
Vol 364 (2) ◽  
pp. 361-368 ◽  
Author(s):  
Mary C. SUGDEN ◽  
Karen BULMER ◽  
Geoffrey F. GIBBONS ◽  
Brian L. KNIGHT ◽  
Mark J. HOLNESS
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Carbohydrate Metabolism ◽  
Plasma Insulin ◽  
Hepatic Glycogen ◽  
Peroxisome Proliferator ◽  
Hepatic Lipogenesis ◽  
Wild Type ◽  
Peroxisome Proliferator Activated Receptor ◽  
Hepatic Lipid

The aim of the present study was to determine whether peroxisome-proliferator-activated receptor-α (PPARα) deficiency disrupts the normal regulation of triacylglycerol (TAG) accumulation, hepatic lipogenesis and glycogenesis by fatty acids and insulin using PPARα-null mice. In wild-type mice, hepatic TAG concentrations increased (P<0.01) with fasting (24h), with substantial reversal after refeeding (6h). Hepatic TAG levels in fed PPARα-null mice were 2.4-fold higher than in the wild-type (P<0.05), increased with fasting, but remained elevated after refeeding. PPARα deficiency also impaired hepatic glycogen repletion (P<0.001), despite normal insulin and glucose levels after refeeding. Higher levels of plasma insulin were required to support similar levels of hepatic lipogenesis de novo (3H2O incorporation) in the PPARα-null mice compared with the wild-type. This difference was reflected by corresponding changes in the relationship between plasma insulin and the mRNA expression of the lipogenic transcription factor sterol-regulatory-element-binding protein-1c, and that of one of its known targets, fatty acid synthase. In wild-type mice, hepatic pyruvate dehydrogenase kinase (PDK) 4 protein expression (a downstream marker of altered fatty acid catabolism) increased (P<0.01) in response to fasting, with suppression (P<0.001) by refeeding. Although PDK4 up-regulation after fasting was halved by PPARα deficiency, PDK4 suppression after refeeding was attenuated. In summary, PPARα deficiency leads to accumulation of hepatic TAG and elicits dysregulation of hepatic lipid and carbohydrate metabolism, emphasizing the importance of precise control of lipid oxidation for hepatic fuel homoeostasis.

scholarly journals Ligand-Activated Peroxisome Proliferator Activated Receptor γ Alters Placental Morphology and Placental Fatty Acid Uptake in Mice

Endocrinology ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 3625-3634 ◽  
Author(s):  
W. Timothy Schaiff ◽  
F. F. (Russ) Knapp ◽  
Yaacov Barak ◽  
Tal Biron-Shental ◽  
D. Michael Nelson ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Acid Uptake ◽  
Acid Transport ◽  
Placental Development ◽  
Peroxisome Proliferator Activated Receptor ◽  
Altered Expression ◽  
Pparγ Agonist

The nuclear receptor peroxisome proliferator activated receptor γ (PPARγ) is essential for murine placental development. We previously showed that activation of PPARγ in primary human trophoblasts enhances the uptake of fatty acids and alters the expression of several proteins associated with fatty acid trafficking. In this study we examined the effect of ligand-activated PPARγ on placental development and transplacental fatty acid transport in wild-type (wt) and PPARγ+/− embryos. We found that exposure of pregnant mice to the PPARγ agonist rosiglitazone for 8 d (embryonic d 10.5–18.5) reduced the weights of wt, but not PPARγ+/− placentas and embryos. Exposure to rosiglitazone reduced the thickness of the spongiotrophoblast layer and the surface area of labyrinthine vasculature, and altered expression of proteins implicated in placental development. The expression of fatty acid transport protein 1 (FATP1), FATP4, adipose differentiation related protein, S3-12, and myocardial lipid droplet protein was enhanced in placentas of rosiglitazone-treated wt embryos, whereas the expression of FATP-2, -3, and -6 was decreased. Additionally, rosiglitazone treatment was associated with enhanced accumulation of the fatty acid analog 15-(p-iodophenyl)-3-(R, S)-methyl pentadecanoic acid in the placenta, but not in the embryos. These results demonstrate that in vivo activation of PPARγ modulates placental morphology and fatty acid accumulation.

scholarly journals Regulation of cardiac fatty acids metabolism in transgenic mice overexpressing bovine GH

2009 ◽  
Vol 201 (3) ◽  
pp. 419-427 ◽  
Author(s):  
Fausto Bogazzi ◽  
Francesco Raggi ◽  
Federica Ultimieri ◽  
Dania Russo ◽  
Aldo D'Alessio ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Transgenic Mice ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Fatty Acid Binding ◽  
Chain Acyl ◽  
Fatty Acids Metabolism ◽  
Key Enzyme ◽  
Key Steps

Cardiac energy metabolism depends mainly on fatty acid (FA) oxidation; however, regulation of FA metabolism in acromegalic (Acro) heart is unknown. The aim of the study was to evaluate cardiac expression of key proteins of FA metabolism in young and elder transgenic mice overexpressing bovine GH Acro. Expression of proteins regulating FA entry into the cells, their uptake by mitochondria and β-oxidation were evaluated by western blot, while FA content by Fourier transform infrared microspectrometry. Regulatory mechanisms of key steps of FA metabolism were also studied. The expression of plasma-membrane FA carriers (fatty acid-binding protein and fatty acid transport protein-1) and acylCoA synthetase was higher in young and lower in elder Acro than in corresponding controls; likewise, expression of cytoplasm to mitochondria-1 (CPT-1), the key enzyme of mitochondrial FA uptake, and that of medium-chain acyl-CoA dehydrogenase and long-chain acyl-CoA dehydrogenase, two regulatory β-oxidation dehydrogenases, followed a similar pattern. FA content was lower in young and higher in elder Acro than in wild-type, suggesting an increased utilisation in young animals. GH regulated expression of key proteins of FA metabolism through changes in peroxisome proliferator-activated receptor α (PPARα) expression, which varied accordingly. GH effect was confirmed by treatment of Acro mice with a receptor antagonist, which abolished changes in key proteins of FA metabolism in young Acro. GH increased phosphorylation of AMP-activated protein kinase and anti-acetyl-CoA-carboxylase, two regulatory kinases, leading to lower CPT-1 inhibition by malonyl-CoA, and intervened in regulating PPARα expression through the ERK 1/2 pathway. In conclusion, chronic GH excess increased FA metabolism in the young age, whereas its action was overwhelmed in elder ages likely by GH-independent mechanisms, leading to reduced expression of key enzyme of FA metabolism.

scholarly journals Mechanisms Mediating the Regulation of Peroxisomal Fatty Acid Beta-Oxidation by PPARα

2021 ◽  
Vol 22 (16) ◽  
pp. 8969
Author(s):  
Mounia Tahri-Joutey ◽  
Pierre Andreoletti ◽  
Sailesh Surapureddi ◽  
Boubker Nasser ◽  
Mustapha Cherkaoui-Malki ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Mammalian Cells ◽  
Atp Synthesis ◽  
Peroxisome Proliferator ◽  
Beta Oxidation ◽  
Peroxisome Proliferator Activated Receptor ◽  
Oxidation Pathway ◽  
Oxidative Phosphorylation Pathway ◽  
Peroxisome Proliferator Response Element ◽  
Peroxisomal Fatty Acid

In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the oxidative phosphorylation pathway for ATP synthesis. At the same time, the peroxisomal β-oxidation pathway participates in cellular thermogenesis. A scientific milestone in 1965 helped discover the hepatomegaly effect in rat liver by clofibrate, subsequently identified as a peroxisome proliferator in rodents and an activator of the peroxisomal fatty acid β-oxidation pathway. These peroxisome proliferators were later identified as activating ligands of Peroxisome Proliferator-Activated Receptor α (PPARα), cloned in 1990. The ligand-activated heterodimer PPARα/RXRα recognizes a DNA sequence, called PPRE (Peroxisome Proliferator Response Element), corresponding to two half-consensus hexanucleotide motifs, AGGTCA, separated by one nucleotide. Accordingly, the assembled complex containing PPRE/PPARα/RXRα/ligands/Coregulators controls the expression of the genes involved in liver peroxisomal fatty acid β-oxidation. This review mobilizes a considerable number of findings that discuss miscellaneous axes, covering the detailed expression pattern of PPARα in species and tissues, the lessons from several PPARα KO mouse models and the modulation of PPARα function by dietary micronutrients.

scholarly journals Effects of Paramylon Extracted from Euglena gracilis EOD-1 on Parameters Related to Metabolic Syndrome in Diet-Induced Obese Mice

Nutrients ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1674 ◽  
Author(s):  
Seiichiro Aoe ◽  
Chiemi Yamanaka ◽  
Kotone Koketsu ◽  
Machiko Nishioka ◽  
Nobuteru Onaka ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Mrna Expression ◽  
Euglena Gracilis ◽  
Ldl Cholesterol ◽  
Growth Parameters ◽  
Postprandial Glucose ◽  
Abdominal Fat ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor

Paramylon (PM), a type of β-glucan, functions like dietary fiber, which has been suggested to exert a protective effect against obesity. We evaluated the potential beneficial effects of PM powder on obesity in mice. Male C57BL/6J mice were fed a high-fat diet supplemented with either 2.5 or 5% PM powder, extracted from Euglena gracilis, for 74 days. Growth parameters, abdominal fat content, serum biochemical markers, hepatic lipid accumulation and hepatic mRNA expression were measured. Dietary supplementation with PM resulted in decreased food efficiency ratios and abdominal fat accumulation. Dose-dependent decreases were observed in postprandial glucose levels, serum low-density lipoprotein (LDL)-cholesterol, and serum secretary immunoglobulin A (sIgA) concentrations. PM supplementation increased peroxisome proliferator-activated receptor α (PPARα) mRNA expression in the liver which is suggested to induce β-oxidation through activation of acyl-coenzyme A oxidase (ACOX), carnitine palmitoyltransferase (CPT) and fatty acid transport protein 2 (FATP2) mRNA expression. Changes in fatty acid metabolism may improve lipid and glucose metabolism. In conclusion, a preventive effect against obesity was observed in mice given a PM-enriched diet. The mechanism is suggested to involve a reduction in both serum LDL-cholesterol levels and the accumulation of abdominal fat, in addition to an improvement in postprandial glucose concentration.

Evaluation of anti-adipogenic active homoisoflavonoids from Portulaca oleracea

2019 ◽  
Vol 74 (9-10) ◽  
pp. 265-273 ◽  
Author(s):  
Jung Im Lee ◽  
Jung Hwan Oh ◽  
Chang-Suk Kong ◽  
Youngwan Seo
Keyword(s):  
Fatty Acid ◽  
Crude Extract ◽  
Lipid Accumulation ◽  
Target Genes ◽  
Adipogenic Differentiation ◽  
Portulaca Oleracea ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Fatty Acid Binding

Abstract This study was performed to isolate antiobesity components from the crude extract of Portulaca oleracea. The crude extract was partitioned into n-hexane, 85% aqueous methanol, n-butanol, and water fractions. Their effects on adipogenic differentiation were evaluated in 3T3-L1 cells. Among the solvent fractions from P. olearacea, the 85% aq. MeOH effectively reduced the levels of lipid accumulation. Further purification of 85% aq. MeOH led to the isolation of the known homoisoflavonoids 1–4, as the active substances. The administration of homoisoflavonoids to adipocyte cells decreased the lipid accumulation and glucose consumption and increased the release of glycerol into culture medium. In particular, homoisoflavonoid 3 effectively down-regulated the adipogenic transcription genes such as peroxisome proliferator activated receptor-γ (PPARγ) and CCAAT/enhancer-binding proteins (C/EBPα), and adipogenic target genes such as fatty acid binding protein 4 (FABP4), fatty acid transport protein 1 (FATP1), and acyl-CoA synthase 1 (ACS1).

scholarly journals Induction of Cardiac Angptl4 by Dietary Fatty Acids Is Mediated by Peroxisome Proliferator-Activated Receptor β/δ and Protects Against Fatty Acid–Induced Oxidative Stress

2010 ◽  
Vol 106 (11) ◽  
pp. 1712-1721 ◽  
Author(s):  
Anastasia Georgiadi ◽  
Laeticia Lichtenstein ◽  
Tatjana Degenhardt ◽  
Mark V. Boekschoten ◽  
Marc van Bilsen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Dietary Fatty Acids ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor

scholarly journals Endogenous Peroxisome Proliferator-Activated Receptor-γ Augments Fatty Acid Uptake in Oxidative Muscle

Endocrinology ◽  
2008 ◽  
Vol 149 (11) ◽  
pp. 5374-5383 ◽  
Author(s):  
Andrew W. Norris ◽  
Michael F. Hirshman ◽  
Jianrong Yao ◽  
Niels Jessen ◽  
Nicolas Musi ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Uptake ◽  
Transport Protein ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Acid Uptake ◽  
Acid Transport ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nonesterified Fatty Acids ◽  
Fatty Acid Transport Protein

In the setting of insulin resistance, agonists of peroxisome proliferator-activated receptor (PPAR)-γ restore insulin action in muscle and promote lipid redistribution. Mice with muscle-specific knockout of PPARγ (MuPPARγKO) develop excess adiposity, despite reduced food intake and normal glucose disposal in muscle. To understand the relation between muscle PPARγ and lipid accumulation, we studied the fuel energetics of MuPPARγKO mice. Compared with controls, MuPPARγKO mice exhibited significantly increased ambulatory activity, muscle mitochondrial uncoupling, and respiratory quotient. Fitting with this latter finding, MuPPARγKO animals compared with control siblings exhibited a 25% reduction in the uptake of the fatty acid tracer 2-bromo-palmitate (P &lt; 0.05) and a 13% increase in serum nonesterified fatty acids (P = 0.05). These abnormalities were associated with no change in AMP kinase (AMPK) phosphorylation, AMPK activity, or phosphorylation of acetyl-CoA carboxylase in muscle and occurred despite increased expression of fatty acid transport protein 1. Palmitate oxidation was not significantly altered in MuPPARγKO mice despite the increased expression of several genes promoting lipid oxidation. These data demonstrate that PPARγ, even in the absence of exogenous activators, is required for normal rates of fatty acid uptake in oxidative skeletal muscle via mechanisms independent of AMPK and fatty acid transport protein 1. Thus, when PPARγ activity in muscle is absent or reduced, there will be decreased fatty acid disposal leading to diminished energy utilization and ultimately adiposity.

Sign in / Sign up

Export Citation Format

Share Document