Urine organic anion increases with age and its effects on renal acid excretion vary with pKa.

IF 2.3 3区 医学 Q3 PHYSIOLOGY
Priya Meera Rawal, Yasin R Badawy, Elaine M Worcester, Fredric L Coe, Megan Prochaska
{"title":"Urine organic anion increases with age and its effects on renal acid excretion vary with pKa.","authors":"Priya Meera Rawal, Yasin R Badawy, Elaine M Worcester, Fredric L Coe, Megan Prochaska","doi":"10.1152/ajpregu.00147.2025","DOIUrl":null,"url":null,"abstract":"<p><p>Findings of falling urine pH with age among stone formers have not been explained by changes in renal function or renal ammonia production with age. We collected and analyzed 245 urines from 190 stone forming subjects (95 male) and 55 normal subjects (18 male), to expand on our previous study using urine titration to explore whether urine organic anion (Uoa) contributes to acid load and rises with age. We stratified our previous titration protocol to include three pKa subranges: 2.70-3.60, 3.61-4.30, and 4.31-7.40, to measure effects of Uoa of differing pKa values on renal acid excretion. We found that Uoa behaves as a metabolic acid, and associates independently and positively with ammonia (<i>p</i> < 0.001). Uoa in pKa range 2.70-3.60 are the principal acid component, and rise with age (<i>p</i> < 0.001), while Uoa in pKa range 4.31-7.40 seem to reflect net alkali excretion when studied in a regression model with the kidney as a reporter organ. When factored per urine creatinine, we found significant age and sex effects of nearly all components of renal acid-base balance. Effects from subject type (stone former vs. normal) were minimal, though we are limited by the oldest tertile having few normals. As acid anions with pKa within 2.70-3.60 are used in the tricarboxylic acid cycle, markers of acid excretion may reflect mitochondrial abnormalities associated with aging.</p>","PeriodicalId":7630,"journal":{"name":"American journal of physiology. Regulatory, integrative and comparative physiology","volume":" ","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"American journal of physiology. Regulatory, integrative and comparative physiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1152/ajpregu.00147.2025","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSIOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

Findings of falling urine pH with age among stone formers have not been explained by changes in renal function or renal ammonia production with age. We collected and analyzed 245 urines from 190 stone forming subjects (95 male) and 55 normal subjects (18 male), to expand on our previous study using urine titration to explore whether urine organic anion (Uoa) contributes to acid load and rises with age. We stratified our previous titration protocol to include three pKa subranges: 2.70-3.60, 3.61-4.30, and 4.31-7.40, to measure effects of Uoa of differing pKa values on renal acid excretion. We found that Uoa behaves as a metabolic acid, and associates independently and positively with ammonia (p < 0.001). Uoa in pKa range 2.70-3.60 are the principal acid component, and rise with age (p < 0.001), while Uoa in pKa range 4.31-7.40 seem to reflect net alkali excretion when studied in a regression model with the kidney as a reporter organ. When factored per urine creatinine, we found significant age and sex effects of nearly all components of renal acid-base balance. Effects from subject type (stone former vs. normal) were minimal, though we are limited by the oldest tertile having few normals. As acid anions with pKa within 2.70-3.60 are used in the tricarboxylic acid cycle, markers of acid excretion may reflect mitochondrial abnormalities associated with aging.

尿液有机阴离子随年龄增加而增加,其对肾酸排泄的影响随pKa的不同而不同。
肾结石患者尿液pH值随年龄下降的现象不能用肾功能或肾氨生成随年龄的变化来解释。我们收集并分析了来自190名结石形成者(95名男性)和55名正常受试者(18名男性)的245份尿液,以扩展我们之前使用尿液滴定的研究,探讨尿液有机阴离子(Uoa)是否有助于酸负荷并随着年龄的增长而增加。为了测量不同pKa值的Uoa对肾酸排泄的影响,我们对之前的滴定方案进行了分层,包括三个pKa亚区:2.70-3.60、3.61-4.30和4.31-7.40。我们发现Uoa表现为一种代谢性酸,并与氨独立且正相关(p < 0.001)。在以肾脏为报告器官的回归模型中,pKa范围2.70-3.60的Uoa是主要的酸成分,并且随着年龄的增长而上升(p < 0.001),而pKa范围4.31-7.40的Uoa似乎反映了净碱排泄。当考虑尿肌酐时,我们发现肾酸碱平衡的几乎所有成分都有明显的年龄和性别影响。受试者类型(前结石vs正常)的影响是最小的,尽管我们受限于最古老的砖块很少正常。由于pKa在2.70-3.60之间的酸性阴离子被用于三羧酸循环,因此酸排泄的标志物可能反映了与衰老相关的线粒体异常。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
CiteScore
5.30
自引率
3.60%
发文量
145
审稿时长
2 months
期刊介绍: The American Journal of Physiology-Regulatory, Integrative and Comparative Physiology publishes original investigations that illuminate normal or abnormal regulation and integration of physiological mechanisms at all levels of biological organization, ranging from molecules to humans, including clinical investigations. Major areas of emphasis include regulation in genetically modified animals; model organisms; development and tissue plasticity; neurohumoral control of circulation and hypertension; local control of circulation; cardiac and renal integration; thirst and volume, electrolyte homeostasis; glucose homeostasis and energy balance; appetite and obesity; inflammation and cytokines; integrative physiology of pregnancy-parturition-lactation; and thermoregulation and adaptations to exercise and environmental stress.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术官方微信