马齿苋多糖对断奶大鼠血清氨基酸代谢谱及肠道菌群影响

EFFECTS OF PORTULACA OLERACEA L.POLYSACCHARIDE ON SERUM AMINO ACID PROFILES AND INTESTINAL FLORA IN WEANED RATS

目的研究马齿苋多糖对断奶大鼠血清中氨基酸代谢及肠道菌群的影响,为马齿苋多糖作为婴幼儿食品添加剂的研究提供理论依据。方法20只断奶SD大鼠[(21±1)日龄]随机分为2组,每组10只。实验动物均饲喂相同的普通饲料,干预组(HD)补充200mg/kg·WB剂量的马齿苋多糖(溶于2ml生理盐水),对照组(Con)补充2ml生理盐水,每日1次,连续28d。试验结束后,16S rDNA高通量测序技术分析肠道菌群结构,靶向代谢组学检测血清中氨基酸水平。结果对照组有1101个特征操作分类单位(OTUs),未分类紫单胞菌属是最大优势菌属、相对丰度为18.65%;马齿苋多糖组有846个特征OTUs,最大优势菌属为帕拉普氏菌属、相对丰度达14.43%。马齿苋多糖可显著性提高断奶大鼠肠道罗姆布茨菌属相对丰度及血清中γ-氨基丁酸和DL-蛋氨酸亚砜含量(P<0.05),显著性降低未分类紫单胞菌属相对丰度及DL-5-羟基赖氨酸、1-甲基-L-组氨酸、乙醇胺、甘氨酸、L-谷氨酰胺和L-高胱氨酸含量(P<0.05)。结论给予断奶大鼠补充饲喂马齿苋多糖可明显影响肠道菌群结构及血清中氨基酸代谢物水平。

Objective To explore the effects of Portulaca oleracea L.polysaccharide(POP)on serum amino acid profiles and intestinal flora in weaned rats,and to provide a theoretical basis for the study of POP as food additive for infants and young children.Methods Weaned SD rats[(21±1)days of age]were evenly randomized into two groups(n=10/group).All rats were fed a regular diet.The rats in the intervention group(HD group)were gavaged with 200mg/kg·BW POP(dissolved in 2 ml normal saline),while the rats in the control group(Con group)were with 2 ml normal saline once a day for 28 days.At the end of the trial,high-throughput sequencing technology(16S rDNA)was used to analyze the composition of intestinal flora,and the levels of amino acids in serum was detected by targeting metabolomics.Results Of the intestinal flora,Con group had 1101 characteristic operational taxonomic units(OTUs),and Porphyromonadaceae_unclassified was the most dominant genus with the relative abundance of 18.65%.HD group had 846 characteristic OTUs,and Paraprevotella was the most dominant genus with the relative abundance of 14.43%.POP significantly upregulated the relative abundance of Romboutsia and the contents ofγ-aminobutyric acid and DL-methionine sulfoxide in serum(P<0.05),and downregulated the relative abundance of Porphyromonadaceae_unclassified and the contents of DL-5-hydroxylysine,1-methyl-L-histidine,ethanolamine,glycine,L-glutamine and L-homocystine(P<0.05).Conclusion Supplementation of Portulaca oleracea L polysaccharide significantly affects the compoition of intestinal flora and the levels of serum amino acids in weaned rats.