染料木黄酮对高能日粮肉鸡胆固醇代谢的影响

为研究染料木黄酮(Gen)对高能日粮肉鸡胆固醇代谢的影响,试验选用11日龄AA肉鸡300只,随机分成5组,每组6个重复,每个重复10只。对照组饲喂基础日粮,2个豆油高能组日粮中增加豆油(5.6%,11~21 d)和(6.6%,22~42 d)使代谢能提高5%,其中1个豆油组添加50 mg/kg Gen;2个猪油高能组增加猪油(5.1%,11~21 d)和(6.2%,22~42 d)使日粮代谢能提高5%,其中1个猪油组日粮中添加50 mg/kg Gen,试验期31 d。结果表明:日粮中添加Gen后豆油高能日粮诱导的肝脏总胆固醇(TC)和血清甘油三酯(TG)显著降低,豆油和猪油高能日粮诱导的血清脂蛋白脂酶(LPL)显著降低(P0.05);添加50 mg/kg Gen可显著降低高能日粮处理组肉鸡肝脏3-羟基-3-甲基戊二酸单酰辅酶A还原酶(HMGCR)的活性及蛋白含量,同时降低固醇调节元件结合蛋白-2(SREBP-2)含量(P0.05);高能日粮提高了HMGCR基因的表达(P0.05),对CYP7A1、SREBP-2等基因的表达无显著影响(P0.05);而Gen可降低高能日粮肉鸡肝脏中上述基因的表达。在本试验条件下,高能日粮中添加50 mg/kg Gen可降低肉鸡血脂及肝脏胆固醇的合成和沉积。

Effects of Genistein on Cholesterol Metabolism in Broilers Fed a High-Energy Diet

To investigate the effects of genistein on cholesterol metabolism in broilers fed a high-energy diet. A total of 300 eleven-day-old health AA male broilers were used for a 31-day experiment. Chicks were randomly assigned into 5 treatments with 6 replicates of 10 males in each group. Chickens in the control group were fed soybean-corn based starter or finisher diets to meet nutrient requirements. Chickens in high energy treatment groups were fed with a high energy with 5% metabolism energy(provided by soybean oil or lard oil) more than the NRC standard from day 11~42 in the presence or absence of genistein(50 mg/kg). Chickens in treatment I and Ⅱ were fed with soybean oil(5.6%, 11~21 d) or(6.6%, 22~42 d) in the presence or absence of genistein(50 mg/kg). Chickens in treatment Ⅲ and Ⅳ were fed with lard oil(5.1%, 11~21 d) or(6.2%, 22~42 d) in the presence or absence of genistein(50 mg/kg). Biochemical analysis showed that high energy density diet induced higher total cholesterol(TC), total glycerol(TG), and lipoprotein lipase(LPL) in serum were significantly abolished by genistein(P <0.05). Genistein tended to increase the high-density lipoproteincholesterol(HDL-C) concentration in the serum. Additionally, high energy density diet induced higher TC in liver was significantly diminished by genisein(P<0.05). High energy density diet induced a pronounced increase in activity of 3-hydroxy-3-methylglutaryl-Co A reductase(HMGCR)(P<0.05). And these effects were significantly diminished by genisein(P<0.05). Genistein(50 mg/kg) significant reduced the content of SREBP-2(P<0.05). The m RNA level of liver 3-hydroxy-3-methylglutaryl-Co A reductase was upregulated by high energy diet, which was markedly reversed by genistein(P<0.05). Energy density had no effect on the expression of CYP7A1 and SREBP-2. However, the expression of CYP7A1 and SREBP-2 were markedly decreased by genistein(P <0.05). In conclusion, 50 mg/kg genistein reduced cholesterol synthesis and deposition both in serum and liver.