Popis: |
Objectives The purpose of this paper is to ascertain the effect and mechanism of Radix Isatidis polysaccharide (RIP) on obesity. Methods High fat diet (HFD)-induced obese rats and the MDI-induced 3T3-L1 adipocyte cells were established to evaluate the ameliorated obesity effect and mechanism from RIP. Key findings Experiments in vivo show that oral administration of RIP has significant preventive effects on HFD-induced obesity and metabolic disorders in rats. With treatment of RIP (20, 40 and 80 mg/kg BW), the body weight, fat accumulation, adipocyte cell size, serum lipid levels and antioxidant enzyme activity were progressively improved. On the other hand, the treatment of 3T3-L1 cells with RIP (25, 50 and 100 mg/L) led to a decrease in lipid accumulation and glucose consumption. In addition, during adipogenesis in 3T3-L1 cells, RIP remarkably down-regulated mRNA levels of peroxisome proliferator-activated receptor-γ (PPARγ), CCAAT/enhancer binding protein-α (C/EBPα), sterol regulatory element-binding protein-1c (SREBP-1c), fatty acid synthase (FAS), acetyl-CoA carboxylase and glycerol-3-phosphate dehydrogenase. Furthermore, after RIP treatment, the protein expression of PPARγ, C/EBPα, FAS, HMG-CoA reductase and acetyl-CoA synthetase-1 (AceCS1) were significantly decreased and the expression of p-AMPK was increased. Conclusion These results highlight the potential of RIP for obesity interventions and suggest that RIP inhibited adipocyte differentiation and lipid synthesis by activating adenosine 5ʹ-monophosphate (AMP)-activated protein kinase (AMPK) signalling pathway and down-regulating the expression of major adipogenic transcription factors, PPARγ, C/EBPα, etc. |