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 ◽  
...  

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.

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 ◽  
...  

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.


2009 ◽  
Vol 201 (3) ◽  
pp. 419-427 ◽  
Author(s):  
Fausto Bogazzi ◽  
Francesco Raggi ◽  
Federica Ultimieri ◽  
Dania Russo ◽  
Aldo D'Alessio ◽  
...  

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.


2019 ◽  
Vol 74 (9-10) ◽  
pp. 265-273 ◽  
Author(s):  
Jung Im Lee ◽  
Jung Hwan Oh ◽  
Chang-Suk Kong ◽  
Youngwan Seo

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).


Endocrinology ◽  
2008 ◽  
Vol 149 (11) ◽  
pp. 5374-5383 ◽  
Author(s):  
Andrew W. Norris ◽  
Michael F. Hirshman ◽  
Jianrong Yao ◽  
Niels Jessen ◽  
Nicolas Musi ◽  
...  

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 < 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.


Nutrients ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 3406
Author(s):  
Seiichiro Aoe ◽  
Chiemi Yamanaka ◽  
Kento Mio

We previously showed that supplementation of a high fat diet with paramylon (PM) reduces the postprandial glucose rise, serum total and LDL cholesterol levels, and abdominal fat accumulation in mice. The purpose of this study was to explore the underlying mechanism of PM using microarray analysis. Male mice (C57BL/BL strain) were fed an experimental diet (50% fat energy) containing 5% PM isolated from Euglena gracilis EOD-1 for 12 weeks. After confirming that PM had an improving effect on lipid metabolism, we assessed ileal and hepatic mRNA expression using DNA microarray and subsequent analysis by gene ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The results suggested that dietary supplementation with PM resulted in decreased abdominal fat accumulation and serum LDL cholesterol concentrations via suppression of the digestion and absorption pathway in the ileum and activation of the hepatic PPAR signaling pathway. Postprandial glucose rise was reduced in mice fed PM, whereas changes in the glucose metabolism pathway were not detected in GO classification and KEGG pathway analysis. PM intake might enhance serum secretory immunoglobulin A concentrations via promotion of the immunoglobulin production pathway in the ileum.


2005 ◽  
Vol 17 (9) ◽  
pp. 125
Author(s):  
S. Jansen ◽  
M. Pantaleon ◽  
P. L. Kaye

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.


Endocrinology ◽  
2006 ◽  
Vol 147 (10) ◽  
pp. 4695-4704 ◽  
Author(s):  
Neus Pedraza ◽  
Meritxell Rosell ◽  
Joan Villarroya ◽  
Roser Iglesias ◽  
Frank J. Gonzalez ◽  
...  

Uncoupling protein-3 (UCP3) is a member of the mitochondrial carrier family expressed preferentially in skeletal muscle and heart. It appears to be involved in metabolic handling of fatty acids in a way that minimizes excessive production of reactive oxygen species. Fatty acids are powerful regulators of UCP3 gene transcription. We have found that the role of peroxisome proliferator-activated receptor-α (PPARα) on the control of UCP3 gene expression depends on the tissue and developmental stage. In adults, UCP3 mRNA expression is unaltered in skeletal muscle from PPARα-null mice both in basal conditions and under the stimulus of starvation. In contrast, UCP3 mRNA is down-regulated in adult heart both in fed and fasted PPARα-null mice. This occurs despite the increased levels of free fatty acids caused by fasting in PPARα-null mice. In neonates, PPARα-null mice show impaired UCP3 mRNA expression in skeletal muscle in response to milk intake, and this is not a result of reduced free fatty acid levels. The murine UCP3 promoter is activated by fatty acids through either PPARα or PPARδ but not by PPARγ or retinoid X receptor alone. PPARδ-dependent activation could be a potential compensatory mechanism to ensure appropriate expression of UCP3 gene in adult skeletal muscle in the absence of PPARα. However, among transcripts from other PPARα and PPARδ target genes, only those acutely induced by milk intake in wild-type neonates were altered in muscle or heart from PPARα-null neonates. Thus, PPARα-dependent regulation is required for appropriate gene regulation of UCP3 as part of the subset of fatty-acid-responsive genes in neonatal muscle and heart.


2020 ◽  
Vol 21 (5) ◽  
pp. 1615 ◽  
Author(s):  
Shi-Cheng Ling ◽  
Mei-Qin Zhuo ◽  
Dian-Guang Zhang ◽  
Heng-Yang Cui ◽  
Zhi Luo

The present study was conducted to explore the mechanism of nano-Zn absorption and its influence on lipid metabolism in the intestine of yellow catfish Pelteobagrus fulvidraco. Compared to ZnSO4, dietary nano-Zn addition increased the triglyceride (TG) content, enzymatic activities of malic enzyme (ME) and fatty acid synthase (FAS), and up-regulated mRNA levels of 6pgd, fas, acca, dgat1, pparγ, and fatp4. Using primary intestinal epithelial cells of yellow catfish, compared to the ZnSO4 group, nano-Zn incubation increased the contents of TG and free fatty acids (FFA), the activities of glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6GPD), ME, and FAS, up-regulated mRNA levels of lipogenic genes (6pgd, g6pd, fas, dgat1, and pparγ), genes of lipid transport (fatp4 and ifabp), and Zn transport genes (znt5, znt7, mt, and mtf1), and increased the protein expression of fatty acid transport protein 4 (FATP4) and peroxisome proliferator activated receptor gamma (PPARγ). Further studies found that nano-Zn absorption was via the clathrin-dependent endocytic mechanism. PPARγ mediated the nano-Zn-induced increase in TG, and nano-Zn increased Zn accumulation and induced TG accumulation by activating the PPARγ pathway and up-regulating lipogenesis.


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