DHA对高脂食物诱导体重增加的保护作用的研究

Protective effects of docosahexaenoic acid supplementation on high-fat diet-induced body weight gain in mice

目的为了探索DHA抑制高脂食物诱导的脂肪增加的机制。方法本研究通过给C57BL/6小鼠饲喂普通食物(C57BL/6 C组),45%高脂食物(C57BL/6 H组)以及45%高脂食物加DHA(每克食物0.2 g的DHA)(FAD3 C组)和(每克食物0.4 g的DHA)(FAD3 H组),20周。第19周测定静止代谢率,20周处死动物检测血清瘦素、甘油三酯的浓度,以及白色脂肪组织和褐色脂肪组织中脂肪分化因子和褐色基因的表达。结果研究发现高脂食物导致C57BL/6 H组的体重、体脂、瘦素和甘油三酯最高(P<0.05)。与C57BL/6 H组相比,DHA降低了体重、体脂、瘦素和甘油三酯(P<0.05),并且有剂量依赖性。在白色脂肪中,DHA降低了高脂食物诱导的PPARγ、CEBPα和SREP1c mRNA表达的增加(P<0.05)。与对照组相比,DHA显著增加白色脂肪组织和褐色脂肪组织中脂肪褐色化基因PGC1αmRNA和UCP1 mRNA表达(P<0.05)。结论食物补充DHA通过增加产热基因的表达,增加静止代谢率、降低白色脂肪和褐色脂肪的脂肪分化基因的表达,从而降低高脂食物诱导的体重增加。

Objective To explore the mechanism by which docosahexaenoic acid(DHA)inhibits the accumulation of adipose tissue lipid in high-fat diet(HFD)-induced body weight gain in C57BL/6 mice.Methods Animals were fed a control diet(C57BL/6 C group),a 45%HFD(C57BL/6 H group)or 45%HFD with 0.2 g DHA(FAD3C)or 0.4 g DHA(FAD3H)per g of food for 20 weeks.Resting metabolic rate was measured at 19 weeks.Visceral adipose and brown adipose tissue were collected for RNA extraction.Lipogenesis-related and fat browning-related gene expression was detected by quantitative PCR.Results A HFD significantly increased(P<0.05)body weight,body fat,and serum leptin and triglyceride(TG)levels in the C57BL/6 H group compared with the C57BL/6 C group.DHA significantly decreased(P<0.05)body weight,fat mass,and levels of serum leptin and TG in the FAD3C and FAD3H groups compared with the C57BL/6 H group.In visceral adipose tissue,DHA significantly downregulated the expression of lipogenesis-related genes,including the CCAAT/enhancer-binding protein,peroxisome proliferator-activated receptor-γ,and sterol regulatory element-binding protein-1C in FAD3H groups compared with the C57BL/6 C group(P<0.05).In visceral adipose and brown adipose tissue,DHA supplementation significantly increased(P<0.05)the expression of fat browning-related genes,including uncoupling protein 1,and peroxisome proliferator-activated receptor coactivator-1a in FAD3H groups compared with the C57BL/6 H group.Conclusions DHA may be used to combat obesity by regulating the resting metabolic rate,levels of leptin,fat and TG,and the expression of browning-related and lipogenesis-related genes.