Liver metabolic changes induced by conjugated linoleic acid in calorie-restricted rats

• Published in: Archives of Endocrinology and Metabolism Vol. 61; no. 1; pp. 45 - 53
• Main Authors: Moraes, Camila de, Oliveira, Camila Andrea de, Amaral, Maria Esméria Corezola do, Landini, Gabriela Arcurio, Catisti, Rosana
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Endocrinologia e Metabologia 01-02-2017; Brazilian Society of Endocrinology and Metabolism
• Subjects: Animals; Caloric Restriction; Energy Metabolism; Fatty Liver - prevention & control; Linoleic Acids, Conjugated - administration & dosage; Lipid Metabolism; Liver - metabolism; Male; metabolism, connexins; metabolism, liver; mitochondria, liver; Rats; Rats, Wistar; restriction, caloric; Time Factors; Trans10cis12-conjugated linoleic acid
• ISSN: 2359-3997; 2359-4292; 2359-4292; 2359-3997
• DOI: 10.1590/2359-3997000000186

Complexes like conjugated linoleic acid (CLA) reduce the percentage of body fat by increasing energy expenditure, fat oxidation, or both. The aim of this study was to verify if CLA is able to mimic caloric restriction (CR), and determine the effects of CLA on liver metabolic profile of young adult male Wistar rats.
We divided 36 animals into the following groups: 1) Control; 2) CLA (1% of daily food intake, 21 days, orogastric intubation); 3) Restr (fed 60% of the diet offered to controls); and 4) CLA Restr. Liver tissues were processed for biochemical and molecular or mitochondrial isolation (differential centrifugation) and blood samples were collected for biochemical analyses.
Treatment of the animals for 21 days with 1% CLA alone or combined with CR increased liver weight and respiration rates of liver mitochondria suggesting significant mitochondrial uncoupling. We observed a decrease in adipose tissue leading to insulin resistance, hyperinsulinemia, and hepatic steatosis due to increased liver cholesterol and triacylglycerol levels, but no significant effects on body mass. The expression of hepatic cellular connexins (43 and 26) was significantly higher in the CLA group compared with the Control or Restr groups.
CLA does not seem to be a safe compound to induce mass loss because it upregulates the mRNA expression of connexins and induces hepatic mitochondrial changes and lipids disorders.