Effects of synthetic conjugated linoleic acid (CLA) or bio-formed CLA as high CLA beef on rat growth and adipose tissue development

2003 ◽  
Vol 83 (3) ◽  
pp. 583-592 ◽  
Author(s):  
P. S. Mir ◽  
E. K. Okine ◽  
L. Goonewardene ◽  
M. L. He ◽  
Z. Mir

Two rat feeding experiments were conducted, concurrently, for 48 d, to determine the effects of feeding synthetic food-grade conjugated linoleic acid (CLA) containing 53% cis 9, trans 11 CLA and 44% trans 10, cis 12 CLA or bio-formed CLA as high CLA beef on adipose tissue development. In exp. 1, 30 (10/diet) weaned male Wistar rats (51 ± 0.65 g) were fed, ad libitum, a control diet, control with sufficient added synthetic CLA to achieve CLA concentrations of 1.1% of diet DM or the control, where the soybean oil in the diet was replaced with sunflower oil. In exp. 2, 20 (10/diet) weaned male Wistar rats (52.5 ± 2.5 g) were fed, ad libitum, diets in which freeze dried beef replaced the casein as the protein source. The meat in the two diets was derived either from steers raised without dietary oil or from beef from steers fed oil to increase CLA content by 144% from 3.36 to 8.20 mg g-1 lipid (high CLA beef). At the end of the experiment the rats were humanely sacrificed and the organs, muscles and the retro-peritoneal and inguinal fat pads were retrieved and weighed. A portion of the fat pad was processed for enumeration of adipocytes while a second portion was used for lipid extraction, and fatty acid composition was determined. In both experiments, diets fed to the rats did not affect rate of growth or carcass, muscle and organ (liver, heart and kidney) weights. In exp. 1, dietary synthetic CLA reduced (P < 0.01) the weight of the retro-peritoneal fat pad and this may have been related to a numerical (-9.8%) but non-significant reduction in feed intake. Although fat pad weight in rats fed sunflower oil was similar to that of rats fed the control diet, the adipocyte number was increased (P < 0.05) by 37%. Dietary supplementation with synthetic CLA, increased (P < 0.05) the CLA concentration in lipids from liver, inguinal fat and retroperitoneal fat of rats. In exp. 2, muscle, organ and fat pad weights were similar for the two meat treatments, but adipocyte number in both pads was lower (P< 0.05) in rats fed the high CLA beef by 40%, which may be a response to dietary CLA and/or a lower protein intake. The lipid from liver and fat tissues of rats fed CLA enhanced beef contained a higher (P < 0.05) CLA concentration than tissues from rats fed the control beef. Data suggest that dietary CLA from either synthetic or high CLA beef may decrease lipid storage potential in fat pads. Key words: Rat, adipose, development, conjugated linoleic acid, high CLA beef

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.


2007 ◽  
Vol 375 (4) ◽  
pp. 283-290 ◽  
Author(s):  
M. M. Romero ◽  
M. Esteve ◽  
J. A. Fernández-López ◽  
M. Alemany

1998 ◽  
Vol 274 (5) ◽  
pp. R1460-R1467 ◽  
Author(s):  
M. DiGirolamo ◽  
J. B. Fine ◽  
K. Tagra ◽  
R. Rossmanith

Adipose tissue grows primarily by a combination of increases in fat cell volume (hypertrophy) and in fat cell number (hyperplasia), but the regional growth pattern of white adipose tissue depots in animal species and in the human is still unclear. In this study we characterized fully the age-related changes in adipose tissue growth, composition, and cellularity of four fat depots of male Wistar rats that varied in age from 7 wk to 15 mo and in body weight from 178 to 808 g. Body weight and the weight of each of the four adipose depots studied (epididymal, mesenteric, subcutaneous inguinal, and retroperitoneal) increased progressively with age and ad libitum feeding. Comparison of the cellularity of the four adipose depots, however, showed remarkable and significant differences in the pattern of growth within the same animals. The cumulative growth of the two intra-abdominal fat depots (mesenteric and epididymal) was due mostly to hypertrophy (increases in cell volume of 83 and 64%, respectively), whereas the growth of the other two depots (retroperitoneal and inguinal) was due predominantly to hyperplasia (increases in cell number of 58 and 65%, respectively). These findings uncover major and unexpected regional differences in the modulation of adipose tissue growth within aging animals fed ad libitum and suggest local, region-specific regulatory controls of this growth.


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.


2001 ◽  
Vol 86 (5) ◽  
pp. 549-555 ◽  
Author(s):  
Hyun S. Park ◽  
Ji H. Ryu ◽  
Yeong L. Ha ◽  
Jung H. Y. Park

One of the objectives of the present study was to investigate whether 1 % conjugated linoleic acid (CLA) in the diet reduced tumour incidence in the colon of 1,2-dimethylhydrazine (DMH)-treated rats. Colon cancer was induced by injecting 6-week-old, male, Sprague–Dawley rats with 15 mg/kg DMH twice per week for 6 weeks. They were fed either 1 % CLA or a control diet ad libitum for 30 weeks. Dietary CLA significantly decreased colon tumour incidence (P<0·05). Our second objective was to investigate whether apoptosis in the colon mucosa of DMH-treated rats was affected by the amount of dietary CLA and whether the changes in apoptosis were related to those in fatty acid-responsive biomarkers. For this purpose, rats were killed after being fed a diet containing 0 %, 0·5 %, 1 % or 1·5 % CLA for 14 weeks. CLA was undetected in the mucosa of rats fed the 0 % CLA diet and increased to 5·9 mg/g phospholipid in rats fed the 0·5 % diet. The apoptotic index estimated by the terminal deoxynucleotidyl transferase-mediated dUTP nick and labelling technique was increased by 251 % and the 1,2-diacylglycerol content was decreased by 57 % in rats fed 0·5 % CLA. No further changes in these variables were observed when CLA in the diet was raised to 1·0 % or 1·5 %. However, dietary CLA decreased mucosal levels of prostaglandin E2, thromboxane B2 and arachidonic acid in a dose-dependent manner. The present data indicate that dietary CLA can inhibit DMH-induced colon carcinogenesis by mechanisms probably involving increased apoptosis.


1997 ◽  
Vol 205 (6) ◽  
pp. 415-418 ◽  
Author(s):  
J. Fritsche ◽  
Magdi M. Mossoba ◽  
Martin P. Yurawecz ◽  
John A. G. Roach ◽  
Najibullah Sehat ◽  
...  

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 ◽  
...  

1995 ◽  
Vol 268 (3) ◽  
pp. R744-R751 ◽  
Author(s):  
T. G. Youngstrom ◽  
T. J. Bartness

When Siberian hamsters are transferred from long summerlike days (LDs) to short winterlike days (SDs) they decrease their body weight, primarily as body fat. These SD-induced decreases in lipid stores are not uniform. Internally located white adipose tissue (WAT) pads are depleted preferentially of lipid, whereas the more externally located subcutaneous WAT pads are relatively spared. These data suggest a possible differential sympathetic neural control over catecholamine-induced lipolysis and that lipolytic rates are greater for internal vs. external WAT pads. Moreover, if these differential rates of lipolysis are due to differential sympathetic nervous system (SNS) drives on the pads, then fat pad-specific catecholaminergic innervation may exist. Therefore, we tested whether inguinal WAT (IWAT; an external pad) and epididymal WAT (EWAT; an internal pad) were innervated differentially. In addition, we tested whether norepinephrine (NE) turnover (TO) reflected the presumed greater SNS drive on EWAT vs. IWAT after SD exposure. Injections of fluorescent tract tracers [Fluoro-Gold or indocarbocyanine perchlorate (DiI)] demonstrated projections from the SNS ganglia T13-L3 to both fat pads. Retrograde labeling revealed a relatively separate pattern of distribution of labeled neurons in the ganglia projecting to each pad. In vivo anterograde transport of DiI resulted in labeling in both IWAT and EWAT that included staining around individual adipocytes and occasionally retrogradely labeled cells. The proportionately greater decrease in EWAT compared with IWAT mass after 5 wk of SD exposure was reflected in greater EWAT NE TO than found in their LD counterparts for this pad.(ABSTRACT TRUNCATED AT 250 WORDS)


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