锌对团头鲂幼鱼血清~1H NMR代谢组的影响

~1H NMR-based metabolomics studies on the effect of Zn in blunt snout bream(Megalobrama amblycephala)

为了发掘团头鲂对锌(Zn)敏感的代谢标志物,以3种Zn含量分别为7.4、32.1和332.4 mg/kg的半纯化饲料(分别标记为L、M和H组),喂养初始体质量为(3.6±0.1)g团头鲂12周,应用1H(氢谱)核磁共振波谱法(1H NMR)检测团头鲂血清代谢物的种类和浓度,再用最小二乘法判别(PLS-DA)和变量重要性(VIP)分析3个处理团头鲂血清的代谢轮廓和主要差异代谢物。结果显示,血清中52种代谢物被定性和定量,其中氨基酸及其衍生物23种、有机酸16种、糖类4种、核酸组分4种、维生素3种和其他组分2种,经PLS-DA和VIP分析,3组的代谢轮廓相异,其中L组血清中脯氨酸、丙氨酸、赖氨酸等8种氨基酸和葡萄糖含量较M组高,H组血清中则有12种氨基酸和葡萄糖含量较M组高。差异代谢物依次为脯氨酸、乳酸、葡萄糖、丙氨酸、赖氨酸、谷氨酰胺、肌酸、反式-4-羟基-L-脯氨酸、牛磺酸、丝氨酸、τ-甲基组氨酸、精氨酸、缬氨酸、蛋氨酸和甘露糖。以上结果显示,饲料中Zn缺乏和过量会抑制团头鲂的氨基酸代谢和糖代谢,脯氨酸、乳酸和葡萄糖是团头鲂对Zn敏感的潜在生物标志物。

A 1 H NMR-based metabolomics approach was used to explore the impact of dietary Zn on the serum metabolic profile of Megalobrama amblycephala. Fish were fed diets containing graded levels of Zn（7.4, 32.1,and 332.4 mg/kg diet; supplied as Zn SO4·7 H2 O） for 12 weeks. We identified 52 metabolites in serum including 23 amino acids or intermediary metabolites, 16 organic acids, 4 sugars, 4 nucleic acids, 3 vitamins and 2 others. Multivariate data analyses（PLS-DA and VIP） showed dietary Zn affected the metabolic profile impartially and these metabolites（such as proline, lactate, glucose, alanine, lysine, glutamine, creatine, trans-4-hydrox-L-proline, taurine, serine, τ-methylhistidine, arginine, valine, methionine and mannose） were identified as charactisteristic metabolites. These metabolites are mainly increased in the groups（7.4 and 332.4 mg/kg diet） compared with the group（32.1 mg/kg）, suggesting that Zn deficiency and excess inhibited amino acid and carbohydrate metabolism. In conclusion, proline, lactate and glucose were found to have potentials for being new biomarkers for Zn nutritional status of M. amblycephala.