Dietary conjugated linoleic acid decreases adipocyte size and favorably modifies adipokine status and insulin sensitivity in obese, insulin-resistant rats.
ABSTRACT Conjugated linoleic acids (CLA) have been shown to alter adiposity in some species with varying effects on insulin resistance. The objective of this 8-week study was to investigate the effects of feeding a CLA mixture (1.5%, wt/wt) on adipocyte size, insulin sensitivity, adipokine status, and adipose lipid composition in fa/fa vs lean Zucker rats. The fa/fa CLA-fed rats had smaller adipocytes and improved insulin sensitivity compared with fa/fa rats fed the control diet. Conjugated linoleic acids did not affect select markers of adipose differentiation, lipid filling, lipid uptake, or oxidation. Dietary CLA, compared with the control diet, reduced circulating leptin and elevated fasting serum adiponectin concentrations in fa/fa rats. Adipose resistin messenger RNA levels were greater in fa/fa CLA-fed rats compared with fa/fa control rats. CLA did not markedly alter adipose phospholipid fatty acid composition, and the changes in the triacylglycerol fatty acid composition reflected a lower delta-9 desaturase index of CLA-fed vs control-fed rats. In conclusion, CLA reduced adipocyte size and favorably modified adipokine status and insulin sensitivity in fa/fa Zucker rats.
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ABSTRACT: Numerous studies have investigated the effects of isolated CLA supplementation on glucose homeostasis in humans and rodents. However, both the amount and relative abundance of CLA isomers in supplemental form are not representative of what is consumed from natural sources. No study to date has examined the effects of altered CLA isomer content within a natural food source. Our goal was to increase the content of the insulin desensitizing CLAt10,c12 isomer relative to the CLAc9,t11 isomer in cow's milk by inducing subacute rumenal acidosis (SARA), and subsequently investigate the effects of this milk fat on parameters related to glucose and insulin tolerance in rats.Lipids in Health and Disease 06/2014; 13(1):101. · 2.31 Impact Factor
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ABSTRACT: In the present study, the effects of long term feeding dietary conjugated linoleic acid (CLA) on growth, liver and perivisceral fat morphology, lipid metabolism enzymes and prostaglandin production potential were assessed. Two hundred and forty-three European sea bass (152.4 ± 1.96 g) were randomly allocated in 9 indoor 1 m3 fiberglass tanks (4.1 kg/m3) and assigned three diets containing graded amounts of CLA (0, 0.5 and 1%) for 20 weeks. Dietary CLA did not affect growth performance or tissue proximate composition although increased the saturated fatty acid fraction in fish fed with 1% CLA in muscle. Muscle and liver fatty acid profiles were slightly altered by CLA inclusion, mainly by the increase of the CLA isomers and by the increase of 18:0 and the decrease of 16:1n-7. Liver lipogenic and lipolytic enzymes were not affected by dietary CLA. Hepatocyte area was reduced in fish fed with 1% of CLA, as well as adipocyte area in fish fed with 0.5% of CLA where adipocyte number by unit of area also increased. Head kidney prostaglandins' production potential was reduced in fish fed with 1% of CLA, having also a negative correlation with dietary CLA level of inclusion. The present results suggest that CLA can be incorporated up to 1% in 150 g European sea bass for 20 weeks without affecting fish performance or enzyme activities and at the time improves liver and adipose tissue morphology.Aquaculture 11/2012; s 368–369:129–137. · 1.83 Impact Factor
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ABSTRACT: Obesity is frequently associated with the development of type 2 diabetes which is firstly characterized by a defect in the response of key metabolic tissues to insulin (insulin resistance). The imbalance in fatty composition of the diet, a low-grade inflammatory state have been described to be involved in the initiation or the amplification of the molecular events involved in this process. The concept of a specific nutritional intervention has emerged as a promising tool against metabolic disorders associated with obesity. In this context, many investigations were conducted to evaluate the potential beneficial impacts of n-3 polyunsaturated fatty acids (n-3 PUFA). The aim of the present review was to summarize the current knowledge about the role of docosahexanoic acid (DHA, 22:6n-3) and eicosapentanoic acid (EPA, 20:5n-3) on key metabolic organs. Only studies aiming to understand the mechanism of actions were selected. The analysis of randomized clinical trial about n-3 PUFA was not considered here. The effects of n-3 PUFA were analyzed in the adipose tissue, the liver, skeletal muscle and the pancreas in the context of obesity and lipid oversupply. Furthermore, in line with recent findings about the role of the modulation of gut microbiota in obesity-related disorders, we summarized the recent findings about the possible link between n-3 PUFA and change in microbiota composition.Journal of physiology and biochemistry 12/2013; · 2.50 Impact Factor