Do teas rich in antioxidants reduce the physicochemical and peroxidative risk factors for calcium oxalate nephrolithiasis in humans? Pilot studies with Rooibos herbal tea and Japanese green tea. Urolithiasis.
Do teas rich in antioxidants reduce the physicochemical and peroxidative risk factors for calcium oxalate nephrolithiasis in humans? Pilot studies with Rooibos herbal tea and Japanese green tea. Urolithiasis.
复制标题
富含抗氧化剂的茶是否可以减少人类草酸钙肾结石的理化和过氧化危险因素？
DOI：
10.1007/s00240-015-0855-4
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发表时间：
2016
期刊：
影响因子：
3.1
通讯作者：
Kohri K
中科院分区：
文献类型：
--
作者：
Rodgers A;Mokoena M;Durbach I;Lazarus J;de Jager S;Ackermann H;Breytenbach I;Okada A;Usami M;Hirose Y;Ando R;Yasui T;Kohri K
一些实验和动物研究表明，富含抗氧化剂的物质可以减少尿液和血液中草酸钙（CaOx）肾结石形成的物理化学和过氧化危险因素。然而，在人类中很少有这样的研究。在目前的试点研究中，两个品种的茶，一个绿色一个来自日本（JGT）和草药一个来自南非（Rooibos）（RT），都富含抗氧化剂，被管理到一组CaOx结石形成者（SF）（n= 8）30天。这两种茶都通过高效液相色谱法分析多酚，并通过等离子体原子和光学发射光谱法分析矿物质。分析24小时尿液（基线和第30天）的成石因素。还测定了每个尿样中的CaOx亚稳极限和晶体成核和生长动力学。通过扫描电子显微镜检查沉积的晶体。采集血样（基线和第30天）。还测定了氧化应激的生物标志物，包括血浆和尿硫代巴比妥酸反应物质（TBARS）和尿N-乙酰-β-D-氨基葡萄糖苷酶（NAG）。两个对照组（CG 1和CG 2）摄入RT 30天后，还研究了尿液理化危险因素，后者由习惯性JGT饮酒者组成。分别使用Wilcoxon符号秩检验和Mann-Whitney检验对配对和独立测量值进行统计分析。在RT和JGT中分别定量了几种黄酮类化合物和儿茶素，证实了这两种茶都是丰富的抗氧化剂来源。发现矿物质含量远低于膳食参考摄入量。对照组或SF中的任何尿理化或过氧化危险因素均无显著变化，但透钙磷石（Bru）的过饱和度（SS）在摄入JGT后在后一组中降低。晶体形态显示出的趋势，从混合的CaOx单和二水合物的一水合物摄入后，每一个茶的变化。由于后一种形式对上皮细胞具有更强的结合亲和力，因此这种作用不是保护性的。对CG 1和CG 2中的理化和过氧化危险因素的分析没有发现两种茶之间协同作用的任何证据。奇怪的是，习惯性JGT对照组的基线风险因素相对于CG 1组显著升高。我们的初步结果表明，摄入RT和JGT并不能降低人类CaOx结石形成的风险因素，但这些发现需要在涉及更大样本量的进一步研究中进行测试。
Several experimental and animal studies have demonstrated that substances rich in antioxidants can reduce the physicochemical and peroxidative risk factors for calcium oxalate (CaOx) renal stone formation in urine and blood. However, there are very few such investigations in humans. In the present pilot study, two varieties of tea, a green one from Japan (JGT) and a herbal one from South Africa (Rooibos) (RT), both rich in antioxidants, were administered to a group of CaOx stone formers (SF) (n= 8) for 30 days. Both teas were analysed for polyphenols by high-performance liquid chromatography and for minerals by plasma atomic and optical emission spectroscopy. 24 h urines (baseline and day 30) were analysed for lithogenic factors. CaOx metastable limits and crystal nucleation and growth kinetics were also determined in each urine sample. Deposited crystals were inspected by scanning electron microscopy. Blood samples were collected (baseline and day 30). Biomarkers of oxidative stress including plasma and urinary thiobarbituric acid reactive substances (TBARS) and urinary N-acetyl-β-D-glucosaminidase (NAG) were also determined. Urinary physicochemical risk factors were also investigated after ingestion of RT for 30 days in two control groups (CG1 and CG2), the latter one of which consisted of habitual JGT drinkers. Statistical analyses were performed using Wilcoxon signed rank tests and Mann–Whitney tests for paired and independent measurements, respectively. Several flavonoids and catechins were quantified in RT and JGT, respectively, confirming that both teas are rich sources of antioxidants. Mineral content was found to be far below dietary reference intakes. There were no significant changes in any of the urinary physicochemical or peroxidative risk factors in the control groups or in SF, except for the supersaturation (SS) of brushite (Bru) which decreased in the latter group after ingestion of JGT. Crystal morphology showed a tendency to change from mixed CaOx mono- and di-hydrate to monohydrate after ingestion of each tea. Since the latter form has a stronger binding affinity for epithelial cells, this effect is not protective. Analysis of the physicochemical and peroxidative risk factors in CG1 and CG2 did not reveal any evidence of a synergistic effect between the two teas. Paradoxically, baseline risk factors in the habitual JGT control group were significantly raised relative to those in CG1. Our preliminary results suggest that ingestion of RT and JGT does not reduce the risk factors for CaOx stone formation in humans, but these findings need to be tested in further studies involving much larger sample sizes.