Effect of Dietary Conjugated Linoleic Acid and Monounsaturated Fatty Acid Content on Pig Muscle and Adipose Tissue Lipase and Esterase Activity

Three levels (0%, 1%, and 2%) of conjugated linoleic acid (CLA) were combined with two levels (low and high) of monounsaturated fatty acids (MUFA) for pig feeding. The activity of neutral lipase (NL), acid lipase (AL), phospholipase (PL), neutral esterase (NE), and acid esterase (AE) was measured in extracts from muscle and subcutaneous adipose tissues. The addition of CLA in the diet only affected the lipolytic activity in muscle, whereas differences in MUFA content of pig diets were mainly responsible for the lipolytic enzyme modifications observed in adipose tissue. Nevertheless, a significant effect of the interaction CLA × MUFA on the activity of several lipolytic enzymes was observed in both tissues. The effect of either linoleic acid (LA) or CLA on the activity of muscle and adipose lipolytic enzymes was determined by in vitro assays. Remarkable inhibitory or activation effects were detected depending on the enzyme and kind of tissue. Keywords: Conjugated linoleic acid (CLA); fatty acids; pig; lipolytic enzymes; muscle; adipose tissue