Abstract

Kidney stones are a common and frequently occurring disease worldwide. Stones can cause urinary tract obstruction, pain, haematuria, and other symptoms. In this study, the relationship between calcium oxalate renal calculi and gut microbiota was considered. The dietary habits of 30 patients with calcium oxalate kidney stones and 30 healthy people were investigated. The 16S rDNA sequences and short-chain fatty acids (SCFAs) in their stool samples were analysed. We identified 5 genera of the gut microbiota as biomarkers for calcium oxalate renal calculi, namely, Bacteroides, Phascolarctobacterium, Faecalibacterium, Akkermansia, and Lactobacillus, with a receiver operating characteristic (ROC) curve value of 0.871 (95% confidence interval (CI) 0.785–0.957). Phascolarctobacterium and Faecalibacterium showed a positive relationship with SCFA synthesis to reduce the risk of kidney stones. Meanwhile, according to the analysis, Lactobacillus spp. made the largest contribution (79%) to prevent kidney stones caused by tea consumption, since tea offers the great parts of oxalate in kidney stone formation. Three strains of Lactobacillus spp. were isolated from stools of a healthy person with a high level of tea consumption who did not suffer from kidney stones. All these strains survived in the colon with supplementation of high concentrations of tea and efficiently degraded oxalic acid (Ca. 50%) in an in vitro colonic simulation. Therefore, a suitable adjustment of the gut microbiota or SCFA concentration enhanced the degradation of oxalate from food, which can be applied to prevent the formation of calcium oxalate renal calculi caused by tea.

Key points

• Five genera, including Lactobacillus, were identified as biomarkers for calcium oxalate renal calculi.

• Lactobacillus is a potential gut bacterium associated with preventing kidney stone formation.

• Isolated Lactobacillus strains have the ability to degrade oxalic acid in vitro.

中文翻译：

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肠道菌群影响日茶摄入量过多引起草酸钙肾结石的形成

摘要

肾结石是世界范围内常见且经常发生的疾病。结石可引起尿路阻塞，疼痛，血尿和其他症状。本研究考虑了草酸钙肾结石与肠道菌群的关系。调查了30名草酸钙肾结石患者和30名健康人的饮食习惯。分析了他们粪便样品中的16S rDNA序列和短链脂肪酸（SCFA）。我们确定了5个属的肠道菌群作为生物标志物为草酸钙肾结石，即拟杆菌，Phascolarctobacterium，Faecalibacterium，Akkermansia和乳杆菌，接收器工作特性（ROC）曲线值为0.871（95％置信区间（CI）0.785–0.957）。杆菌杆菌和费卡杆菌与SCFA合成呈正相关，以减少肾结石的风险。同时，根据分析，乳酸杆菌属。预防茶摄入引起的肾结石的贡献最大（79％），因为茶在肾结石的形成中提供了大量草酸。三种乳酸菌spp。从健康的人的大便中分离出来，这些人的茶摄入量很高，没有肾结石。在体外结肠模拟中，所有这些菌株都在结肠中存活，并补充了高浓度的茶并有效降解了草酸（约50％）。因此，适当调节肠道菌群或SCFA浓度可增强食物中草酸盐的降解，可用于防止由茶引起的草酸钙肾结石的形成。

关键点

•包括乳杆菌在内的五个属被鉴定为草酸钙肾结石的生物标志物。

•乳酸杆菌是与预防肾结石形成相关的潜在肠道细菌。

•分离的乳酸杆菌菌株具有体外降解草酸的能力。