Effects of Conjugated Linoleic Acid, Fish Oil and Soybean Oil on PPARs (α & γ) mRNA Expression in Broiler Chickens and Their Relation to Body Fat Deposits

Abstract

An experiment was conducted on broiler chickens to study the effects of different dietary fats (Conjugated linoleic acid (CLA), fish oil, soybean oil, or their mixtures, as well as palm oil, as a more saturated fat), with a as fed dose of 7% for single fat and 3.5 + 3.5% for the mixtures, on Peroxisome Proliferator-Activated Receptors (PPARs) gene expression and its relation with body fat deposits. The CLA used in this experiment was CLA LUTA60 which contained 60% CLA, so 7% and 3.5% dietary inclusions of CLA LUTA60 were equal to 4.2% and 2.1% CLA, respectively. Higher abdominal fat pad was found in broiler chickens fed with a diet containing palm oil compared to chickens in the other experimental groups (P ≤ 0.05). The diets containing CLA resulted in an increased fat deposition in the liver of broiler chickens (P ≤ 0.05). The only exception was related to the birds fed with diets containing palm oil or fish oil + soybean oil, where contents of liver fat were compared to the CLA + fish oil treatment. PPARγ gene in adipose tissue of chickens fed with palm oil diet was up-regulated compared to other treatments (P ≤ 0.001), whereas no significant differences were found in adipose PPARγ gene expression between chickens fed with diets containing CLA, fish oil, soybean oil or the mixture of these fats. On the other hand, the PPARα gene expression in liver tissue was up-regulated in response to the dietary fish oil inclusion and the differences were also significant for both fish oil and CLA + fish oil diets compared to the diets with palm oil, soybean oil or CLA as the only oil source (P ≤ 0.001). In conclusion, the results of present study showed that there was a relationship between the adipose PPARγ gene up-regulation and abdominal fat pad deposition for birds fed with palm oil diet, while no deference was detected in n-3 and n-6 fatty acids, as well as CLA on PPARγ down regulation in comparison to a more saturated fat. When used on its own, fish oil was found to be a more effective fat in up-regulating hepatic PPARα gene expression and this effect was related to a less fat deposition in liver tissue. A negative correlation coefficient (−0.3) between PPARα relative gene expression and liver tissue fat content confirm the anti-lipogenic effect of PPARα, however, the change in these parameters was not completely parallel.

Conjugated linoleic acid: A potent fatty acid linked to animal and human health

“…On the other hand, Suksombat et al (2007) reported that the reduced abdominal fat pad in birds fed dietary CLA was not accompanied by any increase in carcass, breast or thigh composition. Royan et al (2011a) confirmed the reduction in abdominal fat by a downregulation of PPAR-γ mRNA expression in the abdominal adipose tissue. The PPAR-γ is the most important transcription factor which regulates lipid metabolism and adipocyte differentiation, and is strongly associated with the abdominal fat deposition in avian species (Sato et al, 2009;Xiong et al, 2010).…”

Dietary supplementation with pioglitazone hydrochloride improves intramuscular fat, fatty acid profile, and antioxidant ability of thigh muscle in yellow‐feathered chickens

“…In numerous explorations of IMF deposition, the most obvious characterization is upregulated peroxisome proliferator activated receptor γ (PPAR γ ) abundance . Pioglitazone hydrochloride (PGZ), a high‐affinity ligand of PPAR γ , therefore interested us .…”

“…In numerous explorations of IMF deposition, the most obvious characterization is upregulated peroxisome proliferator activated receptor (PPAR ) abundance. 5,6 Pioglitazone hydrochloride (PGZ), a high-affinity ligand of PPAR , therefore interested us. 7 In studies of ruminants, intramuscular adipose deposition has already been demonstrated to be increased by dietary supplementation with PGZ.…”

Effects of the replacement of corn oil with linseed oil on fatty acid composition and the expression of lipogenic genes in broiler chickens

“…Apart from being an important macronutrient, dietary fat has recently gained much prominence for its role in regulating gene expression in poultry (Royan et al 2011;Zhang et al 2011;Jing et al 2013). LPIN1, LPIN2, WDTC1/ADIPOSE, and △-6 fatty acid desaturase (FADS2) were reported as lipid metabolism genes in human and mouse.…”