Evidence for functional G-coupled protein receptors 43 and 120 in subcutaneous and intramuscular adipose tissue of Angus crossbred steers

2021 ◽  
Author(s):  
Lindsay Westbrook ◽  
Bradley J Johnson ◽  
Gyoungok Gang ◽  
Kentaro Toyonaga ◽  
Jinhee Hwang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oleic Acid ◽  
Palmitic Acid ◽  
Volatile Fatty Acids ◽  
Ex Vivo ◽  
Acetate Incorporation ◽  
Camp Production ◽  
Protein Ratio ◽  
Muscle Section

Abstract We conducted three independent experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP-activated protein kinase-alpha (AMPKα) protein expression and cAMP concentrations differently in i.m. and s.c. adipose tissue. Experiment 1: Oleic acid (18:1n-9) decreased phosphorylated AMPKα protein (p-AMPKα) and the p-AMPKα/AMPKα protein ratio in i.m. preadipocytes, increased the p-AMPKα/AMPKα protein ratio in bovine satellite cells, and had no effect in s.c. preadipocytes. Experment 2: Ex vivo explants from the 5 th-8 th longissimus thoracic rib muscle section of Angus crossbred steers were cultured 48 h in media containing 0.25 µM ciglitizone, 5 mM glucose, and 5 mM acetate, in the absence or presence of 100 µM oleic acid. Oleic acid increased acetate incorporation into fatty acids and GPR43 gene expression in i.m. adipose tissue (P < 0.05), but oleic acid had no effect on fatty acid synthesis or GPR43 expression in s.c. adipose tissue. Experiment 3: Fresh s.c. and i.m. adipose tissue from the 5 th-8 th longissimus thoracic rib muscle section of Angus crossbred steers was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were pre-incubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10 -3, 10 -2.3, and 10 -3 M) in the absence or presence of 100 μM oleic acid or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10 -2 M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis.

PSIV-14 Evidence for functional G-coupled protein receptors 43 and 120 in subcutaneous and intramuscular adipose tissue of Angus crossbred steers

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 293-293
Author(s):  
Lindsay Westbrook ◽  
Stephen Smith ◽  
Gyoungok Gang
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oleic Acid ◽  
Palmitic Acid ◽  
Volatile Fatty Acids ◽  
Camp Production ◽  
Protein Receptor ◽  
Protein Receptors ◽  
Dietary Strategies ◽  
Muscle Section

Abstract We conducted experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP concentrations differently in i.m. and s.c. adipose tissue, which would be dependent on GPR receptor populations in the adipose tissue sites. Fresh s.c. and i.m. adipose tissue from the 5th-8th longissimus thoracic rib muscle section of Angus crossbred steers (approximately 20 mo of age) was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were pre-incubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10–3, 10–2.3, and 10–3 M) in the absence or presence of 100 μM oleic acid (18:1 n-9) or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10–2 M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis. Further research may allow producers to increase marbling with exacerbating carcass fatness through pharmacological or dietary strategies.

scholarly journals High rates of [1-14C]acetate incorporation into the lipid of isolated spinach chloroplasts

1976 ◽  
Vol 158 (3) ◽  
pp. 593-601 ◽  
Author(s):  
P G Roughan ◽  
C R Slack ◽  
R Holland
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Palmitic Acid ◽  
Free Fatty Acids ◽  
Acid Synthesis ◽  
Polar Lipids ◽  
Acetate Incorporation ◽  
Spinach Chloroplasts ◽  
Triton X

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.

scholarly journals Triacylglycerol biosynthesis in rat adipose-tissue homogenates

1976 ◽  
Vol 159 (3) ◽  
pp. 571-577 ◽  
Author(s):  
W W Christie ◽  
M L Hunter ◽  
R G Vernon
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oleic Acid ◽  
Linoleic Acid ◽  
Stearic Acid ◽  
Palmitic Acid ◽  
Positional Distribution ◽  
Triacylglycerol Biosynthesis ◽  
Tissue Homogenates ◽  
Rat Adipose Tissue

The optimum cofactor requirements for triacylglycerol biosynthesis in rat adipose-tissue homogenates containing mitochondrial, microsomal and cytosolic fractions were investigated. In general the optimum concentrations of cofactors for triacylglycerol biosynthesis were found to differ from those for total fatty acid esterification. The results provided further evidence for the key role of phosphatidate phosphohydrolase in the regulation of triacylglycerol biosynthesis. Albumin was included in the incubation medium to permit the use of concentrations of added fatty acids that would swamp the effects of endogenous fatty acids. The addition of albumin had little effect on the incorporation of palmitic acid and stearic acid into lipids including triacylglycerols. By contrast, a critical concentration of albumin (about 60 μM) was required before incorporation of oleic acid or linoleic acid into triacylglycerols occurred. The system was used to study the incorporation of different 1-14C-labelled fatty acids from a mixture of unesterified fatty acids [palmitic acid 30%; stearic acid 10%; oleic acid 40%; linoleic acid 20% (molar percentages)] separately into the positions 1,2 and 3 of triacyl-sn-glycerols. In general the stereo-specific distribution of the labelled fatty acids incorporated into triacylglycerols paralleled the normal distribution of fatty acids within rat adipose-tissue triacylglycerols, suggesting that the specificities of the relevant acyltrasferases have the major role in determining the positional distribution of fatty acids within triacylglycerols.

scholarly journals Effect of fatty acid chain length and saturation on the gastrointestinal handling and metabolic disposal of dietary fatty acids in women

1999 ◽  
Vol 81 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Amanda E. Jones ◽  
Michael Stolinski ◽  
Ruth D. Smith ◽  
Jane L. Murphy ◽  
Stephen A. Wootton
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Stearic Acid ◽  
Palmitic Acid ◽  
Chain Length ◽  
Time Course ◽  
Absorbed Dose ◽  
Dietary Fatty Acids ◽  
Fatty Acid Chain ◽  
Degree Of Unsaturation

The gastrointestinal handling and metabolic disposal of [1-13C]palmitic acid, [1-13C]stearic acid and [1-13C]oleic acid administered within a lipid–casein–glucose–sucrose emulsion were examined in normal healthy women by determining both the amount and nature of the13C label in stool and label excreted on breath as13CO2. The greatest excretion of13C label in stool was in the stearic acid trial (9.2 % of administered dose) whilst comparatively little label was observed in stool in either the palmitic acid (1.2 % of administered dose) or oleic acid (1.9 % of administered dose) trials. In both the palmitic acid and oleic acid trials, all of the label in stool was identified as being present in the form in which it was administered (i.e. [13C]palmitic acid in the palmitic acid trial and [13C]oleic acid in the oleic acid trial). In contrast, only 87 % of the label in the stool in the stearic acid trial was identified as [13C]stearic acid, the remainder was identified as [13C]palmitic acid which may reflect chain shortening of [1-13C]stearic acid within the gastrointestinal tract. Small, but statistically significant, differences were observed in the time course of recovery of13C label on breath over the initial 9 h of the study period (oleic acid = palmitic acid > stearic acid). However, when calculated over the 24 h study period, the recovery of the label as13CO2was similar in all three trials (approximately 25 % of absorbed dose). These results support the view that chain length and degree of unsaturation may influence the gastrointestinal handling and immediate metabolic disposal of these fatty acids even when presented within an emulsion.

scholarly journals Antagonism Between Saturated and Unsaturated Fatty Acids in ROS Mediated Lipotoxicity in Rat Insulin-Producing Cells

2015 ◽  
Vol 36 (3) ◽  
pp. 852-865 ◽  
Author(s):  
Wiebke Gehrmann ◽  
Wiebke Würdemann ◽  
Thomas Plötz ◽  
Anne Jörns ◽  
Sigurd Lenzen ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Palmitic Acid ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
H2o2 Production ◽  
Β Cell ◽  
Specific Expression ◽  
Insulin Producing Cells ◽  
H2o2 Formation

Background/Aims: Elevated levels of non-esterified fatty acids (NEFAs) are under suspicion to mediate β-cell dysfunction and β-cell loss in type 2 diabetes, a phenomenon known as lipotoxicity. Whereas saturated fatty acids show a strong cytotoxic effect upon insulin-producing cells, unsaturated fatty acids are not toxic and can even prevent toxicity. Experimental evidence suggests that oxidative stress mediates lipotoxicity and there is evidence that the subcellular site of ROS formation is the peroxisome. However, the interaction between unsaturated and saturated NEFAs in this process is unclear. Methods: Toxicity of rat insulin-producing cells after NEFA incubation was measured by MTT and caspase assays. NEFA induced H2O2 formation was quantified by organelle specific expression of the H2O2 specific fluorescence sensor protein HyPer. Results: The saturated NEFA palmitic acid had a significant toxic effect on the viability of rat insulin-producing cells. Unsaturated NEFAs with carbon chain lengths >14 showed, irrespective of the number of double bonds, a pronounced protection against palmitic acid induced toxicity. Palmitic acid induced H2O2 formation in the peroxisomes of insulin-producing cells. Oleic acid incubation led to lipid droplet formation, but in contrast to palmitic acid induced neither an ER stress response nor peroxisomal H2O2 generation. Furthermore, oleic acid prevented palmitic acid induced H2O2 production in the peroxisomes. Conclusion: Thus unsaturated NEFAs prevent deleterious hydrogen peroxide generation during peroxisomal β-oxidation of long-chain saturated NEFAs in rat insulin-producing cells.

Effect of increasing stearoyl coenzyme A desaturase mRNA concentrations using forage and concentrate diets on the fatty acid composition of ovine adipose tissue

2002 ◽  
Vol 2002 ◽  
pp. 206-206 ◽  
Author(s):  
Z.C.T.R. Daniel ◽  
R.J. Wynn ◽  
A.M. Salter ◽  
P.J. Buttery
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Stearic Acid ◽  
Acid Composition ◽  
Coenzyme A ◽  
Saturated Fatty Acids ◽  
Mrna Levels

Compared to meat from other animals lamb contains high levels of saturated fat, particularly stearic acid which comprises 18% of the total fatty acids (Enser et al, 1996). This stearic acid can be desaturated in the tissue by stearoyl coenzyme A desaturase (SCD) to produce oleic acid. In sheep SCD is produced from a single gene and the levels of SCD mRNA in the tissue correlate well with oleic acid (Ward et al, 1998, Barber et al, 2000) suggesting that an upregulation of SCD activity may increase the relative proportions of unsaturated and saturated fatty acids and so significantly improve the nutritional quality of sheep meat. Our recent studies have shown that insulin increases SCD mRNA levels and monounsaturated fatty acid synthesis in cultured ovine adipose tissue explants (Daniel et al, 2001). The present study was designed to investigate whether feeding a diet believed to manipulate SCD mRNA concentrations would significantly alter the fatty acid composition of lamb.

Effect of aging on lipid composition and metabolism in the adipose tissues of the rat

1961 ◽  
Vol 201 (3) ◽  
pp. 540-546 ◽  
Author(s):  
William Benjamin ◽  
Alfred Gellhorn ◽  
Mary Wagner ◽  
Harold Kundel
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Palmitic Acid ◽  
Subcutaneous Fat ◽  
Lipid Synthesis ◽  
Pentose Phosphate ◽  
Acid Oxidation ◽  
Acetate Incorporation ◽  
Adipose Tissues

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.

scholarly journals FATTY ACIDS COMPOSITION OF TOCTE (JUGLANS NEOTROPICA DIELS) WALNUT FROM ECUADOR

2018 ◽  
Vol 11 (2) ◽  
pp. 395 ◽  
Author(s):  
Vilcacundo E ◽  
Alvarez M ◽  
Silva M ◽  
Carpio C ◽  
Morales D ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Linoleic Acid ◽  
Stearic Acid ◽  
Palmitic Acid ◽  
Linolenic Acid ◽  
Lipid Content ◽  
Methyl Esters ◽  
Total Lipid Content ◽  
Fatty Acids Composition

 Objective: The aim of this study was to determine the fatty acids composition in a tocte seeds oil (Juglans neotropica Diels) sample cultivated in Ecuador.Methods: Tocte oil was obtained from tocte seeds using the cold pressing method. Fatty acids analysis was carried out using the gas chromatography method with a mass selective detector (GC/MSD) and using the database Library NIST14.L to identify the compounds.Results: Methyl esters fatty acids were identified from tocte (J. neotropica Diels) walnut using the GC–MS analytical method. The total lipid content of tocte walnuts seeds of plants cultivated in Ecuador was of 49.01% of the total lipid content on fresh weight. Fatty acids were analyzed as methyl esters on a capillary column DB-WAX 122-7062 with a good separation of palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. The structure of methyl esters fatty acids was determined using the GC–MS. Tocte walnut presents 5.05% of palmitic acid, 2.26% of stearic acid, 19.50% of oleic acid, 65.81% of linoleic acid, and 2.79% linolenic acid of the total content of fatty acids in tocte oil. Fatty acids content reported in this study were similar to the data reported for other walnuts seeds.Conclusions: Tocte seeds are a good source of monounsaturated and polyunsaturated fatty acids. Tocte oil content oleic acid and with a good content of ɷ6 α-linoleic and ɷ3 α-linolenic. Tocte walnut can help reduce risk cardiovascular diseases in Ecuador for their good composition of fatty acids.

scholarly journals S-acylation modulates the function of the apical sodium-dependent bile acid transporter in human cells

2020 ◽  
Vol 295 (14) ◽  
pp. 4488-4497 ◽  
Author(s):  
Alexander L. Ticho ◽  
Pooja Malhotra ◽  
Christopher R. Manzella ◽  
Pradeep K. Dudeja ◽  
Seema Saksena ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Bile Acid ◽  
Palmitic Acid ◽  
Unsaturated Fatty Acids ◽  
Hek293 Cells ◽  
Metabolic Labeling ◽  
Sodium Dependent ◽  
Bile Acid Transporter ◽  
Acid Transporter

The ileal apical sodium-dependent bile acid transporter (ASBT) is crucial for the enterohepatic circulation of bile acids. ASBT function is rapidly regulated by several posttranslational modifications. One reversible posttranslational modification is S-acylation, involving the covalent attachment of fatty acids to cysteine residues in proteins. However, whether S-acylation affects ASBT function and membrane expression has not been determined. Using the acyl resin-assisted capture method, we found that the majority of ASBT (∼80%) was S-acylated in ileal brush border membrane vesicles from human organ donors, as well as in HEK293 cells stably transfected with ASBT (2BT cells). Metabolic labeling with alkyne–palmitic acid (100 μm for 15 h) also showed that ASBT is S-acylated in 2BT cells. Incubation with the acyltransferase inhibitor 2-bromopalmitate (25 μm for 15 h) significantly reduced ASBT S-acylation, function, and levels on the plasma membrane. Treatment of 2BT cells with saturated palmitic acid (100 μm for 15 h) increased ASBT function, whereas treatment with unsaturated oleic acid significantly reduced ASBT function. Metabolic labeling with alkyne–oleic acid (100 μm for 15 h) revealed that oleic acid attaches to ASBT, suggesting that unsaturated fatty acids may decrease ASBT's function via a direct covalent interaction with ASBT. We also identified Cys-314 as a potential S-acylation site. In conclusion, these results provide evidence that S-acylation is involved in the modulation of ASBT function. These findings underscore the potential for unsaturated fatty acids to reduce ASBT function, which may be useful in disorders in which bile acid toxicity is implicated.

Sign in / Sign up

Export Citation Format

Share Document