Poster Theater Flash Session
Carotenoids and Retinoids (CARIG)
Objectives : To explore whether lutein could activate Sirtuin 1 and up-regulate hormone-sensitive lipase (ATGL) and adipose triglyceride lipase (HSL) and then further improve lipid metabolism in liver and abdominal tissues.
Methods : Animals were randomly divided into two groups after acclimation for 5 d. One group was fed a normal diet (ND) (n =20), while the other group was fed a high fat diet (HFD) (n = 20) for 12 d to induce lipid metabolism disturbance. Based on total cholesterol, the rats fed the ND or HFD were then divided into 2 groups respectively, including four groups: ND, ND+LUT, HFD, HFD+LUT, administered by 25 mg/kg·bw /day lutein for the next 5 weeks. At the end of experiment, all rats were euthanized.
Results : (1) Lutein supplementation significantly decreased the body weight (P < 0.05) and lipid deposition of abdominal fat (P < 0.05) in HFD+LUT; (2) Lutein supplementation significantly decreased hepatic lipid accumulation in hepatic Oil Red O stain (P < 0.01). In abdominal tissues, lutein supplementation markedly brought down the frequence of bigger adipocypes and mean area in HFD+LUT in Hematoxylin and eosin (H&E) stain, quantified by counting 100 cells per rat in every group (P < 0.001). (3) In liver, the excessive lipid accumulation notably suppressed the expression of SIRT1, Peroxisome proliferator-activated receptor-α (PPARα) and Carnitine palmitoyltransferase 1A (CPT1A), whereas lutein supplementation substantially increased their expression (P< 0.01, P< 0.01, P< 0.05). Meanwhile, the lower ATGL expression level were restored to normal level with lutein treated (P< 0.05) and then the ratio of p-HSL/HSL was dramatically enhanced in HFD+LUT whereby lutein supplementation (P< 0.01). (4) In abdominal tissues, lutein supplementation prominently increased the protein contents of SIRT1 both in ND+LUT (P< 0.01) and HFD (P< 0.01). The excessive lipid accumulation in abdominal fat notably repressed the expression of ATGL and ratio of p-HSL/HSL (P< 0.05, P< 0.05). Lutein supplementation revealed an outstanding effect on counteracting the shift caused by high diet feeding (P < 0.001, P < 0.05).
Conclusions : Lutein has positive effects on accelerating lipid lipolysis via the modulation of activating of SIRT1 and up-regulating ATGL and HSL in liver and abdominal tissues.
Funding Sources : This work was supported by the National Natural Science Foundation of China (No.81172657 and No.81573149).