Effect of high fat and high sucrose feeding on lipogenesis by isolated rat intestinal cells

1983 ◽  
Vol 61 (6) ◽  
pp. 340-345 ◽  
Author(s):  
A. C. Wilson ◽  
R. C. Goldstein ◽  
A. R. Conn ◽  
P. T. Kuo

Lipid synthesis was studied in intestinal mucosal cells isolated from rats fed a high fat or a high sucrose diet. The cells actively incorporated 14C(1)-labeled free fatty acids into glycerolipids([1-14C]acetate was utilized for both fatty acid and cholesterol synthesis), while [14C(U)]glucose label was found in cholesterol and in the glycerol moiety of glycerolipids, but not in fatty acids. Sucrose feeding resulted in increased acetate incorporation into cholesterol, but not into fatty acids while the high fat diet markedly depressed the incorporation of acetate. In contrast, fat feeding increased both glucose and fatty acid incorporation into glycerolipids, as well as glucose incorporation into cholesterol. Using the incorporation of glucose into lipid glycerol as an estimate of the phosphatidic acid pathway, it was found that this pathway was stimulated by both fat and carbohydrate feeding. The results suggest that differences in the regulation of cholesterol and glycerolipid synthesis in the intestine compared with adipose tissue and liver may relate to the role of intestine in synthesizing lipoproteins for lipid transport.

1986 ◽  
Vol 235 (1) ◽  
pp. 25-31 ◽  
Author(s):  
J Browse ◽  
N Warwick ◽  
C R Somerville ◽  
C R Slack

The kinetics of [1-14C]acetate incorporation in Arabidopsis thaliana L. (Heyn) showed almost equal labelling of phosphatidylcholine (PC) and diacylgalactosylglycerol (DGG) at early times and the transfer of radioactivity from PC to DGG and diacyldigalactosylglycerol (DDG) at longer times. These kinetics demonstrated the parallel operation of the prokaryotic and eukaryotic pathways of lipid synthesis [Roughan & Slack (1982) Annu. Rev. Plant Physiol. 33, 97-132] in this tissue. At 2 h after the application of [1-14C]acetate, more than 85% of the radioactivity at the sn-2 position of each chloroplast lipid was in 16-carbon fatty acids. However, after 60 h, molecular species containing labelled C18 fatty acids at position sn-2 and presumably derived from microsomal PC made a large contribution (20-70%) to each chloroplast lipid except phosphatidylglycerol. These findings are consistent with the contention that the chain length of the fatty acid at the sn-2 position of glycerol is an accurate predictor of whether a particular lipid molecule has been synthesized by the prokaryotic or eukaryotic pathway. At 30 min after the start of [1-14C]acetate labelling, only 12.3% of the radioactivity in PC was in saturated fatty acids, but the proportion increased steadily to 24.3% after 142 h. It is suggested that steps involved in the conversion of PC to chloroplast lipids on the eukaryotic pathway discriminate against palmitate-containing species. The step involved does not appear to be transfer of PC to the chloroplast because extrachloroplastic and chloroplast membranes purified from Arabidopsis mesophyll protoplasts each contained PC with a fatty acid composition similar to that of the same lipid from leaves. Positional analysis of unlabelled lipids, together with the information summarized above, is used to construct a quantitative scheme of the fluxes through the prokaryotic and eukaryotic pathways during lipid synthesis in Arabidopsis. This scheme shows that 38% of the fatty acids synthesized de novo in the chloroplast enter the prokaryotic pathway in the chloroplast envelope. Of the 62% which are exported as acyl-CoA species to enter the eukaryotic pathway, 56% (34% of the total) are returned to complete synthesis of the chloroplast's complement of glycerolipids.


1983 ◽  
Vol 214 (2) ◽  
pp. 443-449 ◽  
Author(s):  
P Grimaldi ◽  
C Forest ◽  
P Poli ◽  
R Negrel ◽  
G Ailhaud

ob17 cells convert into adipose-like cells when maintained in the presence of physiological concentrations of insulin and tri-iodothyronine. After this conversion, insulin removal from differentiated ob17 cells gives within 24-48 h a large decrease in fatty acid synthetase, glycerol 3-phosphate dehydrogenase and acid:CoA ligase activities, as well as in the rate of fatty acid synthesis determined by [14C]acetate incorporation into lipids. All parameters are restored by insulin addition to initial values within 24-48 h. Dose-response curves of insulin on the restoration of glycerol 3-phosphate dehydrogenase activity and of fatty acid synthesis give half-maximally effective concentrations close to 1 nM, in agreement with the affinity for insulin of the insulin receptors previously characterized in these cells. Immunotitration experiments indicate that the changes in the specific activity of fatty acid synthetase are due to parallel changes in the cellular enzyme content. Therefore the ob17 cell line should be a useful model to study the long-term effects of insulin on the modulation of lipid synthesis in adipose cells.


2011 ◽  
Vol 106 (4) ◽  
pp. 491-501 ◽  
Author(s):  
Manar Aoun ◽  
Francoise Michel ◽  
Gilles Fouret ◽  
Audrey Schlernitzauer ◽  
Vincent Ollendorff ◽  
...  

Accumulation of muscle TAG content and modification of muscle phospholipid fatty acid pattern may have an impact on lipid metabolism, increasing the risk of developing diabetes. Some polyphenols have been reported to modulate lipid metabolism, in particular those issued from red grapes. The present study was designed to determine whether a grape polyphenol extract (PPE) modulates skeletal muscle TAG content and phospholipid fatty acid composition in high-fat–high-sucrose (HFHS) diet-fed rats. Muscle plasmalemmal and mitochondrial fatty acid transporters, GLUT4 and lipid metabolism pathways were also explored. The PPE decreased muscle TAG content in HFHS/PPE diet-fed rats compared with HFHS diet-fed rats and induced higher proportions of n-3 PUFA in phospholipids. The PPE significantly up-regulated GLUT4 mRNA expression. Gene and protein expression of muscle fatty acid transporter cluster of differentiation 36 (CD36) was increased in HFHS diet-fed rats but returned to control values in HFHS/PPE diet-fed rats. Carnitine palmitoyltransferase 1 protein expression was decreased with the PPE. Mitochondrial β-hydroxyacyl CoA dehydrogenase was increased in HFHS diet-fed rats and returned to control values with PPE supplementation. Lipogenesis, mitochondrial biogenesis and mitochondrial activity were not affected by the PPE. In conclusion, the PPE modulated membrane phospholipid fatty acid composition and decreased muscle TAG content in HFHS diet-fed rats. The PPE lowered CD36 gene and protein expression, probably decreasing fatty acid transport and lipid accumulation within skeletal muscle, and increased muscle GLUT4 expression. These effects of the PPE are in favour of a better insulin sensibility.


2009 ◽  
Vol 81 (3) ◽  
pp. 453-466 ◽  
Author(s):  
Cláudia M. Oller do Nascimento ◽  
Eliane B. Ribeiro ◽  
Lila M. Oyama

Approximately 40% of the total energy consumed by western populations is represented by lipids, most of them being ingested as triacylglycerols and phospholipids. The focus of this review is to analyze the effect of the type of dietary fat on white adipose tissue metabolism and secretory function, particularly on haptoglobin, TNF-α, plasminogen activator inhibitor-1 and adiponectin secretion. Previous studies have demonstrated that the duration of the exposure to the high-fat feeding, amount of fatty acid present in the diet and the type of fatty acid may or may not have a significant effect on adipose tissue metabolism. However, the long-term or short-term high fat diets, especially rich in saturated fatty acids, probably by activation of toll-like receptors, stimulated the expression of proinflammatory adipokines and inhibited adiponectin expression. Further studies are needed to investigate the cellular mechanisms by which dietary fatty acids affect white adipose tissue metabolism and secretory functions.


2004 ◽  
Vol 286 (5) ◽  
pp. G822-G832 ◽  
Author(s):  
Anniek Werner ◽  
Rick Havinga ◽  
Folkert Kuipers ◽  
Henkjan J. Verkade

Essential fatty acid (EFA) deficiency during cholestasis is mainly due to malabsorption of dietary EFA ( 23 ). Theoretically, dietary phospholipids (PL) may have a higher bioavailability than dietary triglycerides (TG) during cholestasis. We developed murine models for EFA deficiency (EFAD) with and without extrahepatic cholestasis and compared the efficacy of oral supplementation of EFA as PL or as TG. EFAD was induced in mice by feeding a high-fat EFAD diet. After 3 wk on this diet, bile duct ligation was performed in a subgroup of mice to establish extrahepatic cholestasis. Cholestatic and noncholestatic EFAD mice continued on the EFAD diet (controls) or were supplemented for 3 wk with EFA-rich TG or EFA-rich PL. Fatty acid composition was determined in plasma, erythrocytes, liver, and brain. After 4 wk of EFAD diet, induction of EFAD was confirmed by a sixfold increased triene-to-tetraene ratio (T/T ratio) in erythrocytes of noncholestatic and cholestatic mice ( P < 0.001). EFA-rich TG and EFA-rich PL were equally effective in preventing further increase of the erythrocyte T/T ratio, which was observed in cholestatic and noncholestatic nonsupplemented mice (12- and 16-fold the initial value, respectively). In cholestatic mice, EFA-rich PL was superior to EFA-rich TG in decreasing T/T ratios of liver TG and PL (each P < 0.05) and in increasing brain PL concentrations of the long-chain polyunsaturated fatty acids (LCPUFA) docosahexaenoic acid and arachidonic acid (each P < 0.05). We conclude that oral EFA supplementation in the form of PL is more effective than in the form of TG in increasing LCPUFA concentrations in liver and brain of cholestatic EFAD mice.


2021 ◽  
Vol 12 ◽  
Author(s):  
Takuro Okamura ◽  
Yoshitaka Hashimoto ◽  
Saori Majima ◽  
Takafumi Senmaru ◽  
Emi Ushigome ◽  
...  

Background and AimsMany nutritional and epidemiological studies have shown that high consumption of trans fatty acids can cause several adverse effects on human health, including cardiovascular disease, diabetes, and cancer. In the present study, we investigated the effect of trans fatty acids on innate immunity in the gut by observing mice fed with a diet high in trans fatty acids, which have been reported to cause dysbiosis.MethodsWe used C57BL6/J mice and fed them with normal diet (ND) or high-fat, high-sucrose diet (HFHSD) or high-trans fatty acid, high-sucrose diet (HTHSD) for 12 weeks. 16S rRNA gene sequencing was performed on the mice stool samples, in addition to flow cytometry, real-time PCR, and lipidomics analysis of the mice serum and liver samples. RAW264.7 cells were used for the in vitro studies.ResultsMice fed with HTHSD displayed significantly higher blood glucose levels and advanced fatty liver and intestinal inflammation, as compared to mice fed with HFHSD. Furthermore, compared to mice fed with HFHSD, mice fed with HTHSD displayed a significant elevation in the expression of CD36 in the small intestine, along with a reduction in the expression of IL-22. Furthermore, there was a significant increase in the populations of ILC1s and T-bet-positive ILC3s in the lamina propria in mice fed with HTHSD. Finally, the relative abundance of the family Desulfovibrionaceae, which belongs to the phylum Proteobacteria, was significantly higher in mice fed with HFHSD or HTHSD, than in mice fed with ND; between the HFHSD and HTHSD groups, the abundance was slightly higher in the HTHSD group.ConclusionsThis study revealed that compared to saturated fatty acid intake, trans fatty acid intake significantly exacerbated metabolic diseases such as diabetes and fatty liver.


1976 ◽  
Vol 158 (3) ◽  
pp. 593-601 ◽  
Author(s):  
P G Roughan ◽  
C R Slack ◽  
R Holland

Spinach chloroplasts, isolated by techniques yielding preparations with high O2- evolving activity, showed rates of light-dependent acetate incorporation into lipids 3-4 fold higher than any previously reported. Incorporation rates as high as 500 nmol of acetate/h per mg of chlorophyll were measured in buffered sorbitol solutions containing only NaHCO3 and [1-14C]acetate, and as high as 800 nmol/h per mg of chlorophyll when 0.13 mM-Triton X-100 was also included in the reaction media. The fatty acids synthesized were predominantly oleic (70-80% of the total fatty acid radioactivity) and palmitic (20-25%) with only minor amounts (1-5%) of linoleic acid. Linolenic acid synthesis was not detected in the system in vitro. Free fatty acids accounted for 70-90% of the radioactivity incorporated and the remainder was shared fairly evenly between 1,2-diacylglycerols and polar lipids. Oleic acid constituted 80-90% of the free fatty acids synthesized, but the diacylglycerols and polar lipids contained slightly more palmitic acid than oleic acid. Triton X-100 stimulated the synthesis of diacylglycerols 3-6 fold, but stimulated free fatty acid synthesis only 1-1.5-fold. Added glycerol 1-phosphate stimulated both the synthesis of diacylglycerols and palmitic acid relative to oleic acid, but did not increase acetate incorporation into total chloroplast lipids. CoA and ATP, when added separately, stimulated acetate incorporation into chloroplast lipids to variable extents and had no effect on the types of lipid synthesized, but when added together resulted in 34% of the incorporated acetate appearing in long-chain acyl-CoA. Pyruvate was a much less effective precursor of chloroplast fatty acids than was acetate.


2020 ◽  
Vol 21 (23) ◽  
pp. 9093
Author(s):  
Xinchi Zhao ◽  
Guiyan Yang ◽  
Xiaoqiang Liu ◽  
Zhongdong Yu ◽  
Shaobing Peng

Walnut (Juglans regia) is known as a promising woody oil crop with abundant polyunsaturated fatty acids in its kernel. However, the regulation mechanism of walnut oil accumulation and fatty acid metabolism is still poorly understood, which restricted the breeding and genetic improvement of high-quality oil-bearing walnuts. To reveal the molecular mechanism of walnut oil accumulation, considering the potential regulation of microRNA (miRNA) in seed development, in this study, the oil content of walnut kernel on the 80th, 100th and 120th day after flowering (DAF) was tested and the corresponding proportions are 11.51%, 40.40% and 53.20%. Between DAF of 80th~120th, the content of stearic acid and oleic acid tended to increase, but the proportion of other fatty acids tended to decrease. Meanwhile, comparative transcriptome and sRNA-seq analysis on three stages (80th, 100th and 120th DAF), found 204 conserved miRNAs and 554 novel miRNAs in walnut kernels, among which 104 key genes related to walnut oil accumulation were screened. The phospholipid:diacylglycerol acyltransferase metabolic pathway may contribute more to oil accumulation in walnut. 16 miRNA-mRNA regulatory modules related to walnut oil accumulation and fatty acid synthesis were constructed. 8 known miRNAs and 9 novel miRNAs regulate 28 genes involved in fatty acid (FA) metabolism and lipid synthesis. Among them, jre-miRn105, jre-miRn434, jre-miR477d and jre-miR156a.2 are key miRNAs that regulate walnut FA synthesis. Jre-miRn411 and jre-miR399a.1 are closely related to oil accumulation. These data provide new insights and lay the foundation for subsequent studies on walnut FA synthesis and oil accumulation.


1961 ◽  
Vol 201 (3) ◽  
pp. 540-546 ◽  
Author(s):  
William Benjamin ◽  
Alfred Gellhorn ◽  
Mary Wagner ◽  
Harold Kundel

Lipid metabolism and chemistry was studied in adipose tissues of the rat from the age of 38 days to 647 days. Aging process was characterized by a marked decrease in lipid synthesis from acetate, a reduction in the proportion of glucose metabolized by the pentose phosphate pathway, and a lower rate of palmitate incorporation into the mixed lipids. Oxidation of palmitic acid to CO2 and release of free fatty acid by epididymal fat was the same in young and old tissues under control conditions; when, however, glucose was absent from the medium or when epinephrine was added, there was a significantly greater rate of palmitic acid oxidation and free fatty acid release by young compared to old adipose tissue. Rate of acetate incorporation into mixed lipids by multiple adipose tissue sites was determined at different ages. Consistently greater rates of lipid biosynthesis were found in the epididymal, perirenal, mesenteric and interscapular adipose tissues than in subcutaneous fat at all ages. Rate of lipid synthesis by the interscapular fat (unlike any of the other depots) remained high at all ages studied. A greater proportion of short chain fatty acids was found in adipose tissues from young rats than in the old. This was related to fatty acid composition of rat milk.


2000 ◽  
Vol 279 (4) ◽  
pp. H1490-H1501 ◽  
Author(s):  
Gary W. Goodwin ◽  
Heinrich Taegtmeyer ◽  

We postulate that metabolic conditions that develop systemically during exercise (high blood lactate and high nonesterified fatty acids) are favorable for energy homeostasis of the heart during contractile stimulation. We used working rat hearts perfused at physiological workload and levels of the major energy substrates and compared the metabolic and contractile responses to an acute low-to-high work transition under resting versus exercising systemic metabolic conditions (low vs. high lactate and nonesterified fatty acids in the perfusate). Glycogen preservation, resulting from better maintenance of high-energy phosphates, was a consequence of improved energy homeostasis with high fat and lactate. We explained the result by tighter coupling between workload and total β-oxidation. Total fatty acid oxidation with high fat and lactate reflected increased availability of exogenous and endogenous fats for respiration, as evidenced by increased long-chain fatty acyl-CoA esters (LCFA-CoAs) and by an increased contribution of triglycerides to total β-oxidation. Triglyceride turnover (synthesis and degradation) also appeared to increase. Elevated LCFA-CoAs caused high total β-oxidation despite increased malonyl-CoA. The resulting bottleneck at mitochondrial uptake of LCFA-CoAs stimulated triglyceride synthesis. Our results suggest the following. First, both malonyl-CoA and LCFA-CoAs determine total fatty acid oxidation in heart. Second, concomitant stimulation of peripheral glycolysis and lipolysis should improve cardiac energy homeostasis during exercise. We speculate that high lactate contributes to the salutary effect by bypassing the glycolytic block imposed by fatty acids, acting as an anaplerotic substrate necessary for high tricarbocylic acid cycle flux from fatty acid-derived acetyl-CoA.


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