Glycolic acid is another byproduct of the oxalate pathway and comes from the conversion of glyoxylic acid. Urinary levels of glycolic acid have most commonly been studied in the rare inborn error of metabolism primary hyperoxaluria type 1 (PH1). PH1 is caused by a deficiency of alanine:glyoxylate aminotransferase (AGT) which converts glyoxylic acid into glycine. When this pathway is blocked, due to inborn error, glyoxylic acid ultimately leads to higher production of glycolic acid and oxalic acid.
Clinically, PH1 results in a similar clinical presentation as PH2 with increased oxalic acid excretion and calcium oxalate deposition (oxalosis). This can ultimately progress to renal calcinosis and kidney failure. Aside from inborn error, a large portion of glycolic acid is derived from metabolism of glycine and hydroxyproline. It has been projected that between 20% and 50% of urinary glycolate comes from hydroxyproline in the form of collagen turnover in the body. Supplementation or recent intake of collagen or collagen-rich foods may influence levels of glycolic acid in the urine. Another important source of glycolic acid is the molecule glyoxal. Glyoxal is derived, in part, from oxidative stress in the forms of lipid peroxidation and protein glycation. The majority of this glyoxal is converted into glycolic acid utilizing glutathione as a cofactor.
References:
Lange JN, Wood KD, Knight J, Assimos DG, Holmes RP. Glyoxal formation and its role in endogenous oxalate synthesis. Adv Urol. 2012;2012:819202 [L]
Danpure CJ, Jennings PR. Peroxisomal alanine:glyoxylate aminotransferase deficiency in primary hyperoxaluria type I. FEBS Lett. 1986;201(1):20-24. [L]
Dietzen DJ, Wilhite TR, Kenagy DN, Milliner DS, Smith CH, Landt M. Extraction of glyceric and glycolic acids from urine with tetrahydrofuran: utility in detection of primary hyperoxaluria. Clin Chem. 1997;43(8 Pt 1):1315-1320. [L]
Barratt TM, Kasidas GP, Murdoch I, Rose GA. Urinary oxalate and glycolate excretion and plasma oxalate concentration. Arch Dis Childhood. 1991;66(4):501-503. [L]
Knight J, Jiang J, Assimos DG, Holmes RP. Hydroxyproline ingestion and urinary oxalate and glycolate excretion. Kidney Int. 2006;70(11):1929-1934. [L]
Rabbani N, Thornalley PJ. Dicarbonyls (glyoxal, methylglyoxal, and 3-deoxyglucosone). Uremic Toxins. 2012:177-192. [L]
Knight J, Wood KD, Lange JN, Assimos DG, Holmes RP. Oxalate Formation From Glyoxal in Erythrocytes. Urology. 2016;88:226. e211-225. [L]
Dindo M, Oppici E, Dell’Orco D, Montone R, Cellini B. Correlation between the molecular effects of mutations at the dimer interface of alanine-glyoxylate aminotransferase leading to primary hyperoxaluria type I and the cellular response to vitamin B(6). J Inher Metab Dis. 2018;41(2):263-275. [L]
Leumann E, Hoppe B, Neuhaus T. Management of primary hyperoxaluria: efficacy of oral citrate administration. Ped Nephrol. 1993;7(2):207-211. [L]
The clinical relevance of low levels of urinary glycolic acid has not been fully explored. Low levels of glycolic acid precursors could potentially explain low levels of this end-product. This could be found in lower overall oxidative stress burden or low collagen turnover. Glycine is also a precursor to the glyoxylase system and could theoretically result in low downstream metabolites, such as glycolic acid.
Understand and improve your laboratory results with our health dashboard.
Upload your lab reports and get your interpretation today.
Our technology helps to understand, combine, track, organize, and act on your medical lab test results.
Extremely high levels of urinary glycolic acid are suspicious of a metabolic defect in the glyoxylate pathway such as in PH1. However, this rare inborn error is commonly diagnosed early in life. To note, Genova’s urinary organic acid testing is not designed for the diagnosis of metabolic inborn errors. However, the enzyme defect responsible for PH1 (AGT) is dependent on vitamin B6 as a cofactor. The extent to which urinary glycolic acid could be a functional indicator of vitamin B6 insufficiency has not been studied, however patients with PH1 have shown improvement with B6 intervention.
Aside from inborn error, higher levels of glycolic acid may be indicative of increased oxidative stress. This is because oxidative stress causes higher levels of glyoxal which is ultimately converted into glycolic acid for excretion utilizing glutathione as a cofactor.
Lower levels of glutathione may promote more conversion of glyoxal to oxalic acid.
Lastly, a large proportion of glycolic acid comes from collagen in the form of hydroxyproline. Consumption of foods high in collagen should be considered with unexplained elevations in glycolic acid. The extent to which accelerated turnover of collagen, such as in catabolic conditions, contributed to urinary glycolic acid has not been studied in the literature.
Interpret Your Lab Results
Upload your lab report, and we'll interpret and provide you with recommendations today.
Get StartedOur specialized data entry service is designed to seamlessly integrate your laboratory results into your private dashboard. Just send in your lab test results—whether it's an image or a file—and our skilled data entry team will handle the rest. We accommodate various file formats like PDFs, JPGs, and Excel.
The first report is complimentary. After that, the data entry service is priced at $15 per report, unless it's part of your subscribed plan. It's an ideal solution whether you have numerous reports to upload or if your schedule doesn't permit self-data entry.
We strive to make the data entry process easy for you. Whether by offering dozens of templates to choose from that pre-populate the most popular laboratory panels or by giving you instant feedback on the entered values. Our data entry forms are an easy, fast, and convenient way to enter the reports yourself. There is no limit on how many lab reports you can upload.
Personal plans
track personal results
Professional Plan
track multiple client's results
$15/month
$250/once
own it for life
$45/month
for health professionals
Personal Account
$15/month
for personal lab results
$250/once
own it for life
Level up your lab report analysis with our Pro plan, built for health practitioners like you.
Health Business Account
$45/month
Unlock additional Pro plans when you sign up.
At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.
11-Eicosenoic, 25-Hydroxyvitamin D, a-Hydroxybutyric Acid, AA/EPA, Alpha Linolenic, alpha-Tocopherol, Aluminum, Arachidic, Arachidonic, Arsenic, Behenic, Beta-Carotene, Cadmium, Calcium, Capric, Coenzyme Q10 (Genova), Copper, Creatinine, Dihomogamma Linolenic (Genova), Docosadienoic (Genova), Docosahexaenoic (Genova), Docosapentaenoic (Genova), Docosatetraenoic (Genova), Eicosadienoic (Genova), Eicosapentaenoic (Genova), EPA/DGLA (Genova), Gamma Linolenic (Genova), gamma-Tocopherol (Genova), Glyceric Acid, Glycolic, Heneicosanoic (Genova), Heptadecanoic (Genova), Hexacosanoic (Genova), LA/DGLA, Lauric (Genova), Lead (Genova), Lignoceric (Genova), Linoleic (Genova), Lipid Peroxides (Genova), Magnesium (Genova), Mead (Genova), Mercury (Genova), Myristic (Genova), Myristoleic (Genova), Nervonic (Genova), Nonadecanoic (Genova), Oleic (Genova), Oxalic Acid, Palmitelaidic, Palmitic (Genova), Palmitoleic (Genova), Pentadecanoic (Genova), Potassium (Genova), Selenium (Genova), Stearic (Genova), Stearic/Oleic, Total C:18 Trans, Tricosanoic (Genova), Triene/Tetraene (Genova), Vaccenic, Vitamin A (Retinol) (Genova), Zinc (Genova)