Contribution of Dietary Oxalate and Oxalate Precursors to Urinary Oxalate Excretion

Kidney stone disease is increasing in prevalence, and the most common stone composition is calcium oxalate. Dietary oxalate intake and endogenous production of oxalate are important in the pathophysiology of calcium oxalate stone disease. The impact of dietary oxalate intake on urinary oxalate excretion and kidney stone disease risk has been assessed through large cohort studies as well as smaller studies with dietary control. Net gastrointestinal oxalate absorption influences urinary oxalate excretion. Oxalate-degrading bacteria in the gut microbiome, especially Oxalobacter formigenes, may mitigate stone risk through reducing net oxalate absorption. Ascorbic acid (vitamin C) is the main dietary precursor for endogenous production of oxalate with several other compounds playing a lesser role. Renal handling of oxalate and, potentially, renal synthesis of oxalate may contribute to stone formation. In this review, we discuss dietary oxalate and precursors of oxalate, their pertinent physiology in humans, and what is known about their role in kidney stone disease.

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Association of urinary sex steroid hormones with urinary calcium, oxalate and citrate excretion in kidney stone formers

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfaa360 ◽

2020 ◽

Author(s):

Daniel G Fuster ◽

Gaétan A Morard ◽

Lisa Schneider ◽

Cedric Mattmann ◽

David Lüthi ◽

...

Keyword(s):

Calcium Oxalate ◽

Kidney Stone ◽

Urinary Calcium ◽

Sex Hormone ◽

Urinary Oxalate ◽

Oxalate Excretion ◽

Stone Formers ◽

17Β Estradiol ◽

Urinary Citrate ◽

Urinary Oxalate Excretion

Abstract Background Sex-specific differences in nephrolithiasis with respect to both distribution of prevalence and stone composition are widely described and may be influenced by sex hormones. Methods We conducted a cross-sectional analysis of the relationship between 24-hour urinary sex hormone metabolites measured by gas chromatography–mass spectrometry with urinary calcium, oxalate and citrate excretion in a cohort of 628 kidney stone formers from a tertiary care hospital in Switzerland, taking demographic characteristics, kidney function and dietary factors into account. Results We observed a positive association of urinary calcium with urinary testosterone and 17β-estradiol. Positive associations of urinary calcium with dehydroepiandrosterone, 5α-DH-testosterone, etiocholanolone, androsterone, and estriol were modified by net gastrointestinal alkali absorption or urinary sulfate excretion. As the only sex hormone, dehydroepiandrosterone was inversely associated with urinary oxalate excretion in adjusted analyses. Urinary citrate correlated positively with urinary testosterone. Associations of urinary citrate with urinary androsterone, 17β-estradiol and estriol were modified by urinary sulfate or sodium, or by sex. Conclusions Urinary androgens and estrogens are significantly associated with urinary calcium and citrate excretion, and associations are in part modified by diet. Our data furthermore reveal dehydroepiandrosterone as a novel factor associated with urinary oxalate excretion in humans.

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Dietary oxalate and kidney stone formation

AJP Renal Physiology ◽

10.1152/ajprenal.00373.2018 ◽

2019 ◽

Vol 316 (3) ◽

pp. F409-F413 ◽

Cited By ~ 13

Author(s):

Tanecia Mitchell ◽

Parveen Kumar ◽

Thanmaya Reddy ◽

Kyle D. Wood ◽

John Knight ◽

...

Keyword(s):

Calcium Oxalate ◽

Stone Formation ◽

Continuous Variable ◽

Urinary Oxalate ◽

Calcium Oxalate Stone ◽

Oxalate Excretion ◽

Urinary Oxalate Excretion ◽

Stone Growth ◽

The Impact ◽

Dietary Oxalate

Dietary oxalate is plant-derived and may be a component of vegetables, nuts, fruits, and grains. In normal individuals, approximately half of urinary oxalate is derived from the diet and half from endogenous synthesis. The amount of oxalate excreted in urine plays an important role in calcium oxalate stone formation. Large epidemiological cohort studies have demonstrated that urinary oxalate excretion is a continuous variable when indexed to stone risk. Thus, individuals with oxalate excretions >25 mg/day may benefit from a reduction of urinary oxalate output. The 24-h urine assessment may miss periods of transient surges in urinary oxalate excretion, which may promote stone growth and is a limitation of this analysis. In this review we describe the impact of dietary oxalate and its contribution to stone growth. To limit calcium oxalate stone growth, we advocate that patients maintain appropriate hydration, avoid oxalate-rich foods, and consume an adequate amount of calcium.

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Lowering urinary oxalate excretion to decrease calcium oxalate stone disease

Urolithiasis ◽

10.1007/s00240-015-0839-4 ◽

2015 ◽

Vol 44 (1) ◽

pp. 27-32 ◽

Cited By ~ 23

Author(s):

Ross P. Holmes ◽

John Knight ◽

Dean G. Assimos

Keyword(s):

Calcium Oxalate ◽

Stone Disease ◽

Urinary Oxalate ◽

Calcium Oxalate Stone ◽

Oxalate Excretion ◽

Urinary Oxalate Excretion

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The effect of dietary hydroxyproline and dietary oxalate on urinary oxalate excretion in cats

Journal of Animal Science ◽

10.2527/jas.2012-6178 ◽

2013 ◽

Author(s):

J. C. Dijcker ◽

E. A. Hagen-Plantinga ◽

D. G. Thomas ◽

Y. Queau ◽

V. Biourge ◽

...

Keyword(s):

Urinary Oxalate ◽

Oxalate Excretion ◽

Urinary Oxalate Excretion ◽

Dietary Oxalate

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Association of dietary fatty acids with urinary oxalate excretion in calcium oxalate stone-formers in their fourth decade

BJU International ◽

10.1046/j.1464-410x.2002.02740.x ◽

2002 ◽

Vol 89 (9) ◽

pp. 842-846 ◽

Cited By ~ 27

Author(s):

Y. Naya ◽

H. Ito ◽

M. Masai ◽

K. Yamaguchi

Keyword(s):

Fatty Acids ◽

Calcium Oxalate ◽

Dietary Fatty Acids ◽

Urinary Oxalate ◽

Calcium Oxalate Stone ◽

Oxalate Excretion ◽

Stone Formers ◽

Fourth Decade ◽

Urinary Oxalate Excretion

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Oxalobacter formigenes Colonization and Oxalate Dynamics in a Mouse Model

Applied and Environmental Microbiology ◽

10.1128/aem.01313-15 ◽

2015 ◽

Vol 81 (15) ◽

pp. 5048-5054 ◽

Cited By ~ 19

Author(s):

Xingsheng Li ◽

Melissa L. Ellis ◽

John Knight

Keyword(s):

Kidney Stones ◽

Host Bacterium ◽

Urinary Oxalate ◽

Oxalobacter Formigenes ◽

Content Type ◽

Oxalate Excretion ◽

Urinary Oxalate Excretion ◽

Dietary Oxalate ◽

Different Levels ◽

Unique Ability

ABSTRACTAnimal and human studies have provided compelling evidence that colonization of the intestine withOxalobacter formigenesreduces urinary oxalate excretion and lowers the risk of forming calcium oxalate kidney stones. The mechanism providing protection appears to be related to the unique ability ofO. formigenesto rely on oxalate as a major source of carbon and energy for growth. However, much is not known about the factors that influence colonization and host-bacterium interactions. We have colonized mice withO. formigenesOxCC13 and systematically investigated the impacts of diets with different levels of calcium and oxalate onO. formigenesintestinal densities and urinary and intestinal oxalate levels. Measurement of intestinal oxalate levels in mice colonized or not colonized withO. formigenesdemonstrated the highly efficient degradation of soluble oxalate byO. formigenesrelative to other microbiota. The ratio of calcium to oxalate in diets was important in determining colonization densities and conditions where urinary oxalate and fecal oxalate excretion were modified, and the results were consistent with those from studies we have performed with colonized and noncolonized humans. The use of low-oxalate purified diets showed that 80% of animals retainedO. formigenescolonization after a 1-week dietary oxalate deprivation. Animals not colonized withO. formigenesexcreted two times more oxalate in feces than they had ingested. This nondietary source of oxalate may play an important role in the survival ofO. formigenesduring periods of dietary oxalate deprivation. These studies suggest that the mouse will be a useful model to further characterize interactions betweenO. formigenesand the host and factors that impact colonization.

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