L-carnitine ameliorates dyslipidemic and hepatic disorders induced by a high-fat diet via regulating lipid metabolism, self-antioxidant capacity, and inflammatory response

• L-carnitine (CNT) reduces serum lipids and improves cholesterol profile in high-fat-diet (HFD) fed mice.
• CNT also reduces liver lipid accumulation and inflammatory responses in HFD fed mice.
• CNT can enhance fatty acid β-oxidation in livers of HFD fed mice.
• CNT is not a powerful antioxidant ingredient in HFD fed mice.

The cardiovascular and liver protection of carnitine (CNT) in a high-fat diet was investigated. Male C57BL/6 mice were divided randomly into four groups: 1) CON: Control, 2) HFD: high-fat diet, 3) CNTL: HFD + 500 mg CNT/kg BW, and 4) CNTH: HFD + 1500 mg CNT/kg BW. After a 25-week experimental period, CNT supplementation reduced (p < 0.05) serum triacylglycerol (TAG), cholesterol (TC) and LDLC/HDLC ratio, and liver TAG contents. CNT supplementation downregulated (p < 0.05) gene expressions of lipogenesis, but upregulated (p < 0.05) gene expressions of cholesterol clearance/catabolism and energy expenditure. Serum trolox equivalent antioxidants capacity (TEAC), and liver glutathione (GSH) contents and glutathione-peroxidase (GPx) activity of HFD fed mice were also increased (p < 0.05) by CNT supplementation. Besides, proinflammation related gene expressions (Tlr4 and Nfκb) and proinflammatory cytokine (TNF-α) contents in livers of HFD fed mice were also decreased (p < 0.05) by CNT supplementation. Furthermore, in comparison with the ameliorative effects of two-dosage CNT treatments on dyslipidemic and hepatic disorders induced by a high-fat diet, low dosage of CNT seems more effective than high dosage of CNT.