海洋胶原肽的分子组成及其降血脂和抗氧化作用研究

目的 测定海洋胶原肽(marine collagen peptide,MCP)的相对分子质量,观察其对实验性高脂血症大鼠的血脂水平和抗氧化酶活性及脂质过氧化产物丙二醛(MDA)含量的影响.方法 采用葡聚糖凝胶层析、高效液相和基质辅助激光解吸电离飞行时间质谱方法对MCP组分进行分离和相对分子质量测定.选用50只健康雄性SD大鼠分成正常对照、高脂模型对照和1.0、3.0、9.0 g/kg MCP组,正常对照组大鼠喂饲普通饲料,高脂模型对照组和MCP组大鼠喂饲高脂饲料(79%基础饲料+10%猪油+10%蛋黄粉+1%胆固醇),MCP组大鼠以灌胃方式连续给予不同剂量的MCP(2 ml/100 g)45 d,测定血脂水平及血清谷胱甘肽过氧化物酶(GSH-Px)活力、超氧化物歧化酶(SOD)活性和MDA含量.结果 MCP的相对分子质量范围为100～860,摄人MCP 45 d后1.0、3.0和9.0 g/kg剂量组大鼠血清总胆固醇(TC)分别为(1.89±0.29)mmol/L、(2.07±0.39)mmol/L和(1.99±0.29)mmol/L,与高脂模型对照组(3.37±0.24)mmol/L相比明显降低;血清低密度脂蛋白胆固醇(LDL-C)水平分别为(0.83±0.16)mmol/L、(1.01±0.35)mmol/L和(0.91±0.26)mmol/L,明显低于高脂模型对照组(2.20±0.34)mmol/L;血清SOD活性分别为(218.6±33.2)U/ml、(242.7±21.4)U/ml和(242.1±44.8)U/ml,与高脂模型对照组(119.7±47.8)U/ml相比有显著升高;动脉粥样硬化指数(AI)分别为1.14±0.22、1.16±0.27和0.99±0.31,明显低于高脂模型对照组(2.27±0.55);抗动脉粥样硬化指数(AAI)分别为0.47±0.04、0.47±0.06和0.51±0.09,与高脂模型对照组(0.31±0.05)相比显著增高;3.0和9.0 g/kg剂量组大鼠血清甘油三酯(TG)水平分别为(0.90±0.15)和(0.86±0.12)mmol/L,明显低于高脂模型对照组(1.18±0.18)mmol/L;9.0g/kgbw MCP组大鼠血清MDA含量(7.1±4.1)nmol/ml明显低于高脂模型对照组(15.9±9.9)nmol/ml.结论 MCP具有降血脂和抗氧化的生物活性,对高脂血症的形成和动脉粥样硬化的发生具有一定的预防作用.

The lipid-lowering and antioxidative effects of marine collagen peptides

OBJECTIVE: To determine the relative molecular mass of marine collagen peptides (MCPs) and investigate the effects of MCPs on serum lipids, anti-oxidative enzymes and malondialdehyde (MDA) in hyperlipidemic rats. METHODS: Sephadex G-25, high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) methods were used to determine the relative molecular mass of MCPs. Then 50 healthy male SD rats were divided into 5 groups, which were normal control (NC) group, hyperlipidemic model control (HC) group and 1.0, 3.0, 9.0 g/kgbw MCPs groups, MCPs were orally administered by gavage to rats in MCPs group for 45 consecutive days (2 ml/100 kgbw per day), and the control rats were given vehicle only, all animals (except NC rats) were fed with a high fat diet composed of 79% basic diet, 10% lard, 10% yolk powder and 1% cholesterol. The levels of serum lipids, the content of MDA and activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) in serum were measured. RESULTS: The levels of serum total cholesterol (TC) in 1.0, 3.0, 9.0 g/kgbw MCPs groups were 1.89 +/- 0.29, 2.07 +/- 0.39 and 1.99 +/- 0.29 mmol/L respectively, each of which was significantly lower than that in HC group (3.37 +/- 0.24 mmol/L); low-density lipoprotein cholesterol (LDL-C) levels in 1.0, 3.0, 9.0 g/kgbw MCPs groups were 0.83 +/- 0.16, 1.01 +/- 0.35 and 0.91 +/- 0.26 mmol/L respectively, each of which was significantly lower than that in HC group(2.20 +/- 0.34 mmol/L); triglyceride (TG) levels in 3.0 and 9.0 g/kgbw MCPs groups (0.90 +/- 0.15 and 0.86 +/- 0.12 mmol/L) were reduced significantly compared with that in HC group (1.18 +/- 0.18 mmol/L); MDA level in 9.0 g/kgbw MCPs group was 7.1 +/- 4.1 nmol/ml, which was significantly lower than that in HC group ( 15.9 +/- 9.9 nmol/ml); and atherogenic index (AI) in hyperlipidemic rats fed with 1.0, 3.0, 9.0 g/kgbw MCPs were 1.14 +/- 0.22, 1.16 +/- 0.27 and 0.99 +/- 0.31 respectively, each of which was significantly lower than that in HC group (2.27 +/- 0.55). The activities of SOD in 1.0, 3.0, 9.0 g/kgbw MCPs groups (218.6 +/- 33.2, 242.7 +/- 21.4 and 242.1 +/- 44.8 U/ml) were obviously increased compared with that in HC group (119.7 +/- 47.8 U/ml), and anti-atherogenic index (AAI) were also increased significantly (0.47 +/- 0.04, 0.47 +/- 0.06, 0.51 +/- 0.09 vs 0.31 +/- 0.05). CONCLUSION: MCPs should have antioxidative and lipid-lowering effects, and might play a preventive role in hyperlipidemia and atherogenesis.