Conjugated linoleic acid (CLA) isomers in human adipose tissue

1997 ◽  
Vol 205 (6) ◽  
pp. 415-418 ◽  
Author(s):  
J. Fritsche ◽  
Magdi M. Mossoba ◽  
Martin P. Yurawecz ◽  
John A. G. Roach ◽  
Najibullah Sehat ◽  
...  
2011 ◽  
Vol 107 (10) ◽  
pp. 1413-1421 ◽  
Author(s):  
V. DeClercq ◽  
C. G. Taylor ◽  
P. Zahradka

Obesity-related hypertension may be caused by activation of the local adipose tissue renin–angiotensin system, resulting in exaggerated production of the vasoconstrictor angiotensin II. Additionally, secretion of adiponectin from adipose tissue, which prevents endothelial dysfunction, is altered in obesity. Consumption of conjugated linoleic acid (CLA) has been shown to modulate cytokine release from adipocytes and positively influence blood pressure in younger rats, but its physiological actions in older models with established hypertension and isomer-specific effects on adipocyte size remain to be determined. Therefore, we investigated the effects of CLA isomers on adipocyte size in relation to blood pressure and adipokine production by hypertrophic adipocytes in older fa/fa Zucker rats with established hypertension. fa/fa Zucker rats were fed with cis(c)9, trans(t)11-CLA or t10, c12-CLA isomers for 8 weeks and compared with lean and obese rats fed with the control diet. Blood pressure and adipocyte size were subsequently measured. Collagenase-isolated adipocytes were size-separated and angiotensinogen and adiponectin protein levels quantified by Western blotting. The t10, c12-CLA group had reduced blood pressure, fewer large adipocytes and increased serum adiponectin. Angiotensinogen was present at higher levels in the large adipocytes, whereas the converse was observed for adiponectin. The beneficial effects of the t10, c12-CLA isomer on blood pressure and adipocyte size in vivo may be due to its ability to reduce the number of large adipocytes, which alters the levels of vasoactive molecules secreted from adipose tissue.


2003 ◽  
Vol 90 (5) ◽  
pp. 915-928 ◽  
Author(s):  
Ewa Ostrowska ◽  
Reg F. Cross ◽  
Morley Muralitharan ◽  
Dale E. Bauman ◽  
Frank R. Dunshea

Conjugated linoleic acids (CLA) have been shown to decrease body fat content in pigs. It is possible that feeding pigs diets rich in CLA may increase carcass lipid CLA to levels that could provide health benefits when included as a part of a healthy diet. Therefore, the aim of the present study was to determine whether dietary CLA supplementation has any effect on the fatty acid composition of subcutaneous and intramuscular adipose tissue in pigs. Thirty-five female cross bred (Large White×Landrace) pigs (initial weight 57·2kg and initial P2 back fat 11·5mm) were used in the present study. Pigs were housed individually and randomly allocated to one of six dietary treatments (0·00, 1·25, 2·50, 5·00, 7·50 and 10·00g CLA55 (55g CLA isomers/100g total fatty acids; Natural Lipids Ltd, Hovdebygda, Norway)/kg) and fed their respective diets for 8 weeks. Twelve CLA isomers in the diet and in pig tissue lipids were separated by Ag+-HPLC. CLA was incorporated at fivefold higher levels in subcutaneous fat as compared with intramuscular fat and in a dose-dependant manner. Overall, the transfer efficiency of CLA was maximized at 5·00g CLA55/kg. However, there was clear selectivity in the uptake or incorporation ofcis,trans-9,11 isomer over thetrans,cis-10,12 isomer. In general, CLA supplementation produced significant changes in skeletal muscle and adipose tissue fatty acid composition, indicating that dietary CLA had a potent affect on lipid transport and metabolismin vivo. Significant increases in myristic, palmitic and palmitoleic acids and a reduction in arachidonic acid were observed, suggesting an alteration in activity of Δ5-, Δ6- and Δ9-desaturases in pig adipose tissue. In conclusion, feeding pigs diets supplemented with CLA increases carcass lipid CLA, but also results in changes in the fatty acid profile in pig fat that could potentially outweigh the benefits of CLA.


2021 ◽  
Vol 22 (6) ◽  
pp. 3227
Author(s):  
Jayasimha Rayalu Daddam ◽  
Harald M. Hammon ◽  
Arnulf Tröscher ◽  
Laura Vogel ◽  
Martina Gnott ◽  
...  

Phosphoproteomics is a cutting-edge technique that can be utilized to explore adipose tissue (AT) metabolism by quantifying the repertoire of phospho-peptides (PP) in AT. Dairy cows were supplemented with conjugated linoleic acid (CLA, n = 5) or a control diet (CON, n = 5) from 63 d prepartum to 63 d postpartum; cows were slaughtered at 63 d postpartum and AT was collected. We performed a quantitative phosphoproteomics analysis of subcutaneous (SC) and omental (OM) AT using nanoUPLC-MS/MS and examined the effects of CLA supplementation on the change in the phosphoproteome. A total of 5919 PP were detected in AT, and the abundance of 854 (14.4%) were differential between CON and CLA AT (p ≤ 0.05 and fold change ± 1.5). The abundance of 470 PP (7.9%) differed between OM and SC AT, and the interaction treatment vs. AT depot was significant for 205 PP (3.5% of total PP). The integrated phosphoproteome demonstrated the up- and downregulation of PP from proteins related to lipolysis and lipogenesis, and phosphorylation events in multiple pathways, including the regulation of lipolysis in adipocytes, mTOR signaling, insulin signaling, AMPK signaling, and glycolysis. The differential regulation of phosphosite on a serine residue (S777) of fatty acid synthase (FASN) in AT of CLA-supplemented cows was related to lipogenesis and with more phosphorylation sites compared to acetyl-coenzyme A synthetase (ACSS2). Increased protein phosphorylation was seen in acetyl-CoA carboxylase 1 (ACACA;8 PP), FASN (9 PP), hormone sensitive lipase (LIPE;6 PP), perilipin (PLIN;3 PP), and diacylglycerol lipase alpha (DAGLA;1 PP) in CLA vs. CON AT. The relative gene expression in the SC and OM AT revealed an increase in LIPE and FASN in CLA compared to CON AT. In addition, the expression of DAGLA, which is a lipid metabolism enzyme related to the endocannabinoid system, was 1.6-fold higher in CLA vs. CON AT, and the expression of the cannabinoid receptor CNR1 was reduced in CLA vs. CON AT. Immunoblots of SC and OM AT showed an increased abundance of FASN and a lower abundance of CB1 in CLA vs. CON. This study presents a complete map of the SC and the OM AT phosphoproteome in dairy cows following CLA supplementation and discloses many unknown phosphorylation sites, suggestive of increased lipid turnover in AT, for further functional investigation.


Lipids ◽  
1998 ◽  
Vol 33 (8) ◽  
pp. 803-809 ◽  
Author(s):  
Martin P. Yurawecz ◽  
John A. G. Roach ◽  
Najibullah Sehat ◽  
Magdi M. Mossoba ◽  
John K. G. Kramer ◽  
...  

2011 ◽  
Vol 56 (No. 1) ◽  
pp. 23-29 ◽  
Author(s):  
M. Czauderna ◽  
J. Kowalczyk ◽  
M. Marounek ◽  
J.P. Michalski ◽  
A.J. Rozbicka-Wieczorek

A new method for the quantification of underivatized conjugated linoleic acid (CLA) isomers and CLA-metabolites by silver ion liquid chromatography (Ag<sup>+</sup>-HPLC) with photodiode array detection (DAD) is described. Conjugated fatty acids (CFA) and sorbic acid as the internal standard (IS) were separated on two 5 &mu;m Chrompac ChromSpher Lipids columns (250 &times; 4.6 mm). Biological samples were hydrolyzed with 1M KOH in methanol and 2M KOH in water at room temperature for 12 h. Hydrolyzates were acidified and the free fatty acids were extracted with dichloromethane. The organic solvent was removed and then the residue was re-dissolved in hexane and centrifuged. The supernatant was injected onto the columns. The mobile phase of 1.6% acetic acid and 0.0125% acetonitrile in hexane was chosen as the optimum mobile phase for fractionation of IS, CLA isomers and CLA-metabolites in all assayed biological samples. The use of two silver ion-exchange columns with direct UV detection (Ag<sup>+</sup>-HPLC-DAD) offers satisfactory precision of the IS quantification and low limits of detection of IS and CLA isomers (0.60 and 0.21&ndash;0.35 ng, respectively). The presented simple Ag<sup>+</sup>-HPLC-DAD method with sorbic acid as the IS can be used for direct determination of underivatized CLA isomers in specimens of animal origin. &nbsp;


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