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Molecules (Basel, Switzerland) Apr 2023Oxalate is a divalent organic anion that affects many biological and commercial processes. It is derived from plant sources, such as spinach, rhubarb, tea, cacao, nuts,... (Review)
Review
Oxalate is a divalent organic anion that affects many biological and commercial processes. It is derived from plant sources, such as spinach, rhubarb, tea, cacao, nuts, and beans, and therefore is commonly found in raw or processed food products. Oxalate can also be made endogenously by humans and other mammals as a byproduct of hepatic enzymatic reactions. It is theorized that plants use oxalate to store calcium and protect against herbivory. Clinically, oxalate is best known to be a major component of kidney stones, which commonly contain calcium oxalate crystals. Oxalate can induce an inflammatory response that decreases the immune system's ability to remove renal crystals. When formulated with platinum as oxaliplatin (an anticancer drug), oxalate has been proposed to cause neurotoxicity and nerve pain. There are many sectors of industry that are hampered by oxalate, and others that depend on it. For example, calcium oxalate is troublesome in the pulp industry and the alumina industry as it deposits on machinery. On the other hand, oxalate is a common active component of rust removal and cleaning products. Due to its ubiquity, there is interest in developing efficient methods to quantify oxalate. Over the past four decades, many diverse methods have been reported. These approaches include electrochemical detection, liquid chromatography or gas chromatography coupled with mass spectrometry, enzymatic degradation of oxalate with oxalate oxidase and detection of hydrogen peroxide produced, and indicator displacement-based methods employing fluorescent or UV light-absorbing compounds. Enhancements in sensitivity have been reported for both electrochemical and mass-spectrometry-based methods as recently as this year. Indicator-based methods have realized a surge in interest that continues to date. The diversity of these approaches, in terms of instrumentation, sample preparation, and sensitivity, has made it clear that no single method will work best for every purpose. This review describes the strengths and limitations of each method, and may serve as a reference for investigators to decide which approach is most suitable for their work.
Topics: Humans; Animals; Oxalates; Calcium Oxalate; Gas Chromatography-Mass Spectrometry; Kidney; Kidney Calculi; Mammals
PubMed: 37049969
DOI: 10.3390/molecules28073206 -
Current Opinion in Nephrology and... Jul 2016Oxalate is an end product of metabolism excreted via the kidney. Excess urinary oxalate, whether from primary or enteric hyperoxaluria, can lead to oxalate deposition in... (Review)
Review
PURPOSE OF REVIEW
Oxalate is an end product of metabolism excreted via the kidney. Excess urinary oxalate, whether from primary or enteric hyperoxaluria, can lead to oxalate deposition in the kidney. Oxalate crystals are associated with renal inflammation, fibrosis, and progressive renal failure. It has long been known that as the glomerular filtration rate becomes reduced in chronic kidney disease (CKD), there is striking elevation of plasma oxalate. Taken together, these findings raise the possibility that elevation of plasma oxalate in CKD may promote renal inflammation and more rapid progression of CKD independent of primary cause.
RECENT FINDINGS
The inflammasome has recently been identified to play a critical role in oxalate-induced renal inflammation. Oxalate crystals have been shown to activate the NOD-like receptor family, pyrin domain containing 3 inflammasome (also known as NALP3, NLRP3, or cryopyrin), resulting in release of IL-1β and macrophage infiltration. Deletion of inflammasome proteins in mice protects from oxalate-induced renal inflammation and progressive renal failure.
SUMMARY
The findings reviewed in this article expand our understanding of the relevance of elevated plasma oxalate levels leading to inflammasome activation. We propose that inhibiting oxalate-induced inflammasome activation, or lowering plasma oxalate, may prevent or mitigate progressive renal damage in CKD, and warrants clinical trials.
Topics: Animals; Disease Progression; Fibrosis; Humans; Inflammasomes; Inflammation; Interleukin-1beta; Kidney; Macrophages; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; Oxalates; Renal Insufficiency, Chronic
PubMed: 27191349
DOI: 10.1097/MNH.0000000000000229 -
Applied and Environmental Microbiology Aug 2021Oxalobacter formigenes, a unique anaerobic bacterium that relies solely on oxalate for growth, is a key oxalate-degrading bacterium in the mammalian intestinal tract.... (Review)
Review
Oxalobacter formigenes, a unique anaerobic bacterium that relies solely on oxalate for growth, is a key oxalate-degrading bacterium in the mammalian intestinal tract. Degradation of oxalate in the gut by plays a critical role in preventing renal toxicity in animals that feed on oxalate-rich plants. The role of in reducing the risk of calcium oxalate kidney stone disease and oxalate nephropathy in humans is less clear, in part due to difficulties in culturing this organism and the lack of studies which have utilized diets in which the oxalate content is controlled. Herein, we review the literature on the 40th anniversary of the discovery of , with a focus on its biology, its role in gut oxalate metabolism and calcium oxalate kidney stone disease, and potential areas of future research. Results from ongoing clinical trials utilizing in healthy volunteers and in patients with primary hyperoxaluria type 1 (PH1), a rare but severe form of calcium oxalate kidney stone disease, are also discussed. Information has been consolidated on strains and best practices to culture this bacterium, which should serve as a good resource for researchers.
Topics: Animals; Gastrointestinal Microbiome; Genomics; Humans; Inactivation, Metabolic; Metabolomics; Nephrolithiasis; Oxalates; Oxalobacter formigenes
PubMed: 34190610
DOI: 10.1128/AEM.00544-21 -
Urolithiasis Dec 2020Measurement of oxalate in the blood is essential for monitoring primary hyperoxaluria patients with progressive renal impairment and on dialysis prior to... (Comparative Study)
Comparative Study
Measurement of oxalate in the blood is essential for monitoring primary hyperoxaluria patients with progressive renal impairment and on dialysis prior to transplantation. As no external quality assurance scheme is available for this analyte, we conducted a sample exchange scheme between six laboratories specifically involved with the investigation of primary hyperoxaluria to compare results. The methodologies compared were gas chromatography/mass spectrometry (GCMS), ion chromatography with mass spectrometry (ICMS), and enzymatic methods using oxalate oxidase and spectrophotometry. Although individual laboratories performed well in terms of reproducibility and linearity, there was poor agreement (absolute values) between centres as illustrated by a longer-term comparison of patient results from two of the participating laboratories. This situation was only partly related to differences in calibration and mainly reflected the lower recoveries seen with the ultrafiltration of samples. These findings lead us to conclude that longitudinal monitoring of primary hyperoxaluria patients with deteriorating kidney function should be performed by a single consistent laboratory and the methodology used should always be defined. In addition, plasma oxalate concentrations reported in registry studies and those associated with the risk of systemic oxalosis in published studies need to be interpreted in light of the methodology used. A reference method and external quality assurance scheme for plasma oxalate analysis would be beneficial.
Topics: Hematologic Tests; Humans; Hyperoxaluria, Primary; Oxalates
PubMed: 32472220
DOI: 10.1007/s00240-020-01197-4 -
Medical Mycology Journal 2015
Topics: Aspergillosis; Aspergillus fumigatus; Calcium Oxalate; Crystallization; Humans; Lung Diseases, Fungal; Male; Middle Aged; Oxalates; Pneumonectomy
PubMed: 25855022
DOI: 10.3314/mmj.56.J1 -
Current Opinion in Nephrology and... Jul 2019The effect of the intestinal microbiome on urine chemistry and lithogenicity has been a popular topic. Here we review the evidence for exposure to antibiotics increasing... (Review)
Review
PURPOSE OF REVIEW
The effect of the intestinal microbiome on urine chemistry and lithogenicity has been a popular topic. Here we review the evidence for exposure to antibiotics increasing the risk of nephrolithiasis.
RECENT FINDINGS
Studies of the intestinal microbiome have focused on Oxalobacter formigenes, an anaerobe that frequently colonizes the human colon. As a degrader of fecal oxalate its presence is associated with lower urinary oxalate, which would be protective against calcium oxalate stone formation. It also appears capable of stimulating colonic oxalate secretion. A recent study showed that antibiotics can eliminate colonization with O. formigenes. In a case-control study, exposure to sulfa drugs, cephalosporins, fluoroquinolones, nitrofurantoin/methenamine, and broad spectrum penicillins prospectively increased the odds of nephrolithiasis. The effect was greatest for those exposed at younger ages and 3-6 months before being diagnosed with nephrolithiasis.
SUMMARY
Recent evidence suggests a possible, causal role of antibiotics in the development of kidney stones. A possible explanation for this finding includes alterations in the microbiome, especially effects on oxalate-degrading bacteria like O. formigenes. Ample reasons to encourage antibiotic stewardship already exist, but the possible role of antibiotic exposure in contributing to the increasing prevalence of kidney stones in children and adults is another rationale.
Topics: Anti-Bacterial Agents; Antimicrobial Stewardship; Gastrointestinal Microbiome; Humans; Kidney Calculi; Oxalates; Oxalobacter formigenes; Risk
PubMed: 31145705
DOI: 10.1097/MNH.0000000000000510 -
Rhode Island Medical Journal (2013) Dec 2023Hyperoxaluria is a clinically relevant metabolic entity that portends a high morbidity burden. Primarily manifesting as kidney stone disease and chronic kidney disease,... (Review)
Review
Hyperoxaluria is a clinically relevant metabolic entity that portends a high morbidity burden. Primarily manifesting as kidney stone disease and chronic kidney disease, advanced hyperoxaluria can also affect major organs, including the brain, heart, liver, bone, and the skin. It is categorized based on etiology into primary and secondary hyperoxaluria. Pathology is attributed to excess de novo oxalate production in the former and multifactorial exogenous oxalate absorption or excess intake of its precursors in the latter. Diagnosis often involves demonstrating elevated urinary oxalate levels, especially in patients with normal kidney function. Here in this review, we will perform an in-depth discussion of various causes of hyperoxaluria and describe treatment options. In view of the significant morbidity burden associated with hyperoxaluria, patients could benefit from heightened clinician awareness to aid in the timely diagnosis and management of this condition.
Topics: Humans; Kidney Calculi; Hyperoxaluria; Oxalates
PubMed: 38015779
DOI: No ID Found -
Scientific Reports Dec 2021The present work focuses on the revealing the patterns of copper oxalates formation under the influence of lichens and fungi by combination of the results of field...
The present work focuses on the revealing the patterns of copper oxalates formation under the influence of lichens and fungi by combination of the results of field studies and model experiments. These findings create the scientific basis for the potential microbial technology applications (ore enrichment, monuments conservation, environment bioremediation, etc.). Copper oxalate moolooite Cu(CO)·HO was discovered in saxicolous lichen Lecidea inops on the weathered chalcopyrite ore of Voronov Bor deposit (Central Karelia, Russia). Bioinspired syntheses of moolooite and wheatleyite NaCu(CO) 2HO with the participation of the microscopic fungi Aspergillus niger (active producer of oxalic acid) were carried out on weathered Cu-ore from the Voronov Bor deposit. It was shown that morphology of moolooite crystals is controlled both by the underlying rock and by the species composition of microorganisms. Iron ions (sourced from the underlying rock) in the crystallization medium inhibits the moolooite formation. The observed intensive dissolution of moolooite crystals are well explained by washing effect of the intratalline solutions which depends on repeatedly dehydration / rehydration cycles in the lichens. Joint interpretation of original and published data shows that moolooite along with other cooper oxalates are biominerals.
Topics: Aspergillus niger; Biochemical Phenomena; Biodegradation, Environmental; Copper; Crystallization; Fungi; Geology; Ions; Iron; Lichens; Microscopy, Electron, Scanning; Oxalates; Oxalic Acid; Sulfides; X-Ray Diffraction
PubMed: 34930985
DOI: 10.1038/s41598-021-03600-5 -
Physiology (Bethesda, Md.) Feb 2012Anion transporters NaS1 (SLC13A1) and Sat1 (SLC26A1) mediate sulfate (re)absorption across renal proximal tubule and small intestinal epithelia, thereby regulating blood... (Review)
Review
Anion transporters NaS1 (SLC13A1) and Sat1 (SLC26A1) mediate sulfate (re)absorption across renal proximal tubule and small intestinal epithelia, thereby regulating blood sulfate levels. Disruption of murine NaS1 and Sat1 genes leads to hyposulfatemia and hypersulfaturia. Sat1-null mice also exhibit hyperoxalemia, hyperoxaluria, and calcium oxalate urolithiasis. This review will highlight the current pathophysiological features of NaS1- and Sat1-null mice resulting from alterations in circulating sulfate and oxalate anion levels.
Topics: Animals; Anion Transport Proteins; Gene Knockout Techniques; Humans; Oxalates; Sulfates
PubMed: 22311966
DOI: 10.1152/physiol.00041.2011 -
World Journal of Microbiology &... Apr 2024Oxalic acid and oxalates are secondary metabolites secreted to the surrounding environment by fungi, bacteria, and plants. Oxalates are linked to a variety of processes... (Review)
Review
Oxalic acid and oxalates are secondary metabolites secreted to the surrounding environment by fungi, bacteria, and plants. Oxalates are linked to a variety of processes in soil, e.g. nutrient availability, weathering of minerals, or precipitation of metal oxalates. Oxalates are also mentioned among low-molecular weight compounds involved indirectly in the degradation of the lignocellulose complex by fungi, which are considered to be the most effective degraders of wood. The active regulation of the oxalic acid concentration is linked with enzymatic activities; hence, the biochemistry of microbial biosynthesis and degradation of oxalic acid has also been presented. The potential of microorganisms for oxalotrophy and the ability of microbial enzymes to degrade oxalates are important factors that can be used in the prevention of kidney stone, as a diagnostic tool for determination of oxalic acid content, as an antifungal factor against plant pathogenic fungi, or even in efforts to improve the quality of edible plants. The potential role of fungi and their interaction with bacteria in the oxalate-carbonate pathway are regarded as an effective way for the transfer of atmospheric carbon dioxide into calcium carbonate as a carbon reservoir.
Topics: Oxalic Acid; Fungi; Bacteria; Biotechnology; Plants; Oxalates; Lignin
PubMed: 38662173
DOI: 10.1007/s11274-024-03973-5