黑木耳肽钙螯合物对后肢去负荷小鼠骨丢失的防护研究

Protective Effect of Auricularia auricula Peptide Chelating with Ca^(2+) on Hindlimb Unloaded Bone Loss of Mouse

目的探究天然产物功能成分与钙离子形成的螯合物对尾吊模拟失重小鼠骨丢失的防护作用。方法首先通过促成骨细胞增殖活性的差异筛选出效果最佳的黑木耳肽段,并对其中功能性成分进行分离纯化。随后建立小鼠尾吊后肢去负荷骨丢失模型,研究了纯化组分的钙离子螯合物对尾吊小鼠股骨干重、股骨指数,骨中无机物、有机物含量,血清中骨代谢相关酶活性的作用。结果黑木耳粗蛋白经胰蛋白酶酶解30 min,所得多肽与钙离子形成的螯合物具有最强的促成骨细胞增殖活性,该肽段中主要功能成分为AP-2。AP-2-Ca2+可显著提高尾吊小鼠骨干重及骨矿物质含量,调节血清碱性磷酸酶(AKP)活力,抑制抗酒石酸酸性磷酸酶(Str ACP)活性增加。不同剂量的AP-2-Ca2+对尾吊小鼠骨丢失具有不同程度的防护作用。结论黑木耳肽钙螯合物对后肢去负荷小鼠骨丢失具有一定程度的防护作用。

Objective To explore the protective effect of functional compositions from natural products chelating with calcium ions upon the hindlimb unloaded bone loss of mouse. Methods The best Auricularia auricula peptide was obtained by comparing the proliferative activity of osteoblast,in which the functional composition was isolated and purified by semi-preparative HPLC. The protective effect of purified functional composition chelating with calcium ions in vivo was studied by establishing a tail-suspended mice model. The bone dry weight,femur index,bone mineral and organic amounts,and the serum enzyme activities related to bone metabolism were determined. Results The enzymatic hydrolysis peptide to be obtained with trypsin enzymolysis for 30 min was chosen as the best peptide,whose chelation had the highest protective rate. AP-2 was indicated as the functional composition,and different doses of AP-2-Ca^（2＋） showed positive effects on disuse bone-loss by improving the bone mineral and regulating the activities of AKP and Str ACP. Conclusion Auricularia auricula peptide chelating with calcium ions performed protective effect on hindlimb unloaded mice to some extent.