Dietary L-theanine supplementation improves antioxidant capacity and lipid metabolism in finishing pigs

Abstract

The objective of this study was to investigate the effects of dietary L-theanine (LTH) supplementation on finishing pigs' antioxidant capacity and lipid metabolism. Results showed that dietary LTH supplementation increased the activity of antioxidant enzymes and decreased the content of malondialdehyde in serum, longissimus dorsi muscle (LD muscle), and liver of finishing pigs (P < 0.05). Dietary LTH supplementation decreased serum low-density lipoprotein cholesterol content and increased high-density lipoprotein cholesterol content (P < 0.05). Moreover, LTH-containing diet decreased the contents of triglyceride and total cholesterol in serum, LD muscle, and liver (P < 0.05). In liver and LD muscle, LTH activated Nrf2-Keap1 signaling pathway, increased mRNA expression levels of genes related to lipolysis and fatty acid oxidation and reduced the expression levels of genes related to adipogenesis (P < 0.05). According to our study, nutritional supplementation with LTH enhanced finishing pigs' antioxidant capacity and lipid metabolism.

Keywords

• Finishing pigs
• L-theanine
• Antioxidant capacity
• Lipid metabolism