Daily Rhythm of Urinary Excretion of Thiodiglycolic Acid (TDGA) in Humans Under Different Health Conditions and Treatment

Abstract

The new simple voltammetric method we described recently was useful in determining thiodiglycolic acid (TDGA) levels in urine samples of people under the effect of some chemicals, victuals, and pharmaceutics. The present pilot study is a continuation of our work devoted to test the general applicability of the method. We have concentrated on the time‐dependent quantitative changes of TDGA excretion into urine of randomly selected volunteers. The TDGA level in all morning samples was the highest in comparison with samples collected during the day. The TDGA level was dependent on the health condition of each person involved. However, a further marked increase of TDGA in the morning urine was generally observed in individuals after cyanocobalamin (vitamin B12) had been administered in the evening the day before urine collection. Vitamin B12 is known to play an important role in the metabolism of one‐ and two‐carbon units, of homocysteine, and of sulfhydryls in general. Certain variations in excretion course of TDGA were evidently due to specific individual metabolic differences. The present results open the way for further experiments with our voltammetric method to provide details of TDGA formation and to use its analysis as a possible diagnostic tool. Supported by the Ministry of Industry and Trade of the Czech Republic (Project No. 1H‐PK/42) and by the Ministry of Education, Youth and Sports of the Czech Republic (Research Projects No. 111100002 and No. 111100005).