基于16SrRNA和非靶向代谢组测序分析益生菌对乳腺癌患者化疗后肠道菌群和代谢物的影响

The Impact of Probiotics on the Gut Microbiota and Metabolites of Breast Cancer Patients after Chemotherapy Was Analyzed Based on 16S rRNA and Untargeted Metabolomics

摘要: 目的：本研究旨在探讨益生菌对乳腺癌患者化疗后肠道菌群及血清代谢物的影响。方法：将34例行AC方案化疗的患者随机分为益生菌组(PT组，n = 17)与安慰剂组(CT组，n = 17)。PT组在化疗基础上口服乳双歧杆菌V9 (每日2 g)，CT组服用安慰剂。于化疗前及首次化疗后21天收集粪便与血液样本，分别进行16S rRNA测序与非靶向代谢组学分析。结果：干预后PT2组肠道菌群Alpha多样性(Observed species、Chao1、ACE及Shannon指数)显著高于CT2组(p < 0.05)，Beta多样性分析显示两组菌群结构显著分离。LEfSe分析表明，PT2组中普拉梭菌、罗伊氏乳杆菌、双歧杆菌属、粪便拟杆菌、肠道拟杆菌及罗斯氏菌属等有益菌相对丰度显著升高。代谢组学分析共筛选出103个显著差异代谢物，KEGG富集分析发现32条显著差异代谢通路，主要涉及嘌呤代谢、精氨酸生物合成、甘氨酸–丝氨酸–苏氨酸代谢、胆汁酸生物合成、α-亚麻酸代谢及牛磺酸代谢等。结论：益生菌干预与化疗后肠道菌群结构改善、有益菌丰度升高及血清代谢谱变化相关，提示其或具减轻化疗相关肠道毒性的潜力，为临床应用提供了微生物–代谢轴层面的依据。

Abstract: Objective: This study aimed to investigate the effects of probiotic supplementation on the gut microbiota and serum metabolites in breast cancer patients following chemotherapy. Methods: Thirty-four patients undergoing AC regimen chemotherapy were randomly assigned to either a probiotic group (PT group, n = 17) or a placebo group (CT group, n = 17). The PT group received oral Bifidobacterium lactis V9 (2 g daily) alongside chemotherapy, while the CT group received a placebo. Fecal and blood samples were collected before the first chemotherapy cycle and 21 days after it. Analyses included 16S rRNA gene sequencing and non-targeted metabolomic profiling. Results: After the intervention, the PT2 group showed significantly higher gut microbiota alpha diversity (Observed species, Chao1, ACE, and Shannon indices) compared to the CT2 group (p < 0.05). Beta diversity analysis revealed a distinct separation in microbial community structure between the two groups. LEfSe analysis indicated a significant increase in the relative abundance of beneficial bacteria in the PT2 group, including Faecalibacterium prausnitzii, Lactobacillus reuteri, Bifidobacterium spp., Bacteroides stercoris, Bacteroides intestinalis, and Roseburia spp. Metabolomic analysis identified 103 significantly differential metabolites, and KEGG enrichment analysis highlighted 32 significantly altered metabolic pathways. These pathways were primarily involved in purine metabolism, arginine biosynthesis, glycine-serine-threonine metabolism, bile acid biosynthesis, α-linolenic acid metabolism, and taurine metabolism. Conclusion: Probiotic intervention was associated with improved gut microbiota structure, increased abundance of beneficial bacteria, and altered serum metabolite profiles in patients after chemotherapy. These findings suggest that probiotics may have the potential to mitigate chemotherapy-related intestinal toxicity, providing preliminary evidence at the microbiota-metabolite axis level to support their clinical application.