Reference urinary biopyrrin level and physiological variation in healthy young adults: relation of stress by learning

Abstract

Background: Biopyrrins are end products of oxidation reactions of bilirubin with reactive oxygen, and urinary biopyrrin (UBP) levels might increase under oxidative stress. The authors examined the reference UBP level for healthy adults and its physiological variation in 40 healthy volunteers recruited from among students of our university (20 students each from third-year and fourth-year), and compared the results with data on 8-hydroxy-2deoxyguanosine (8OHdG). Methods: UBP and 8OHdG levels could be considered as oxidative stress markers. The UBP levels were measured with a competitive ELISA kit using biopyrrin antibody 24G7, according to the manufacturer's protocol. 8OHdG levels were measured with a Highly Sensitive 8-OHdG Check kit. UBP and 8OHdG measurements were performed in triplicate and means values calculated. For both parameters, creatinine (Cr) correction was performed using urinary creatinine levels measured by an enzymatic method. Results: A comparison of the UBP levels between different grades revealed that the third-year students under high stress from clinical training and other course work tended to have a higher UBP level than fourth-year students. Therefore, we compared the current UBP levels in fourth-year students (samples collected in 2018) with their UBP level when they were in the third-year (samples collected in 2017) to examine the annual change. We found that the UBP level in 2017 samples was significantly higher than that in 2018 samples (P < 0.05). No difference in the 8OHdG level. Additionally, no effect of menstrual stress on the UBP level was observed. Conclusions: These results suggest that the UBP levels may be related to school-related stress and menstruation has no effects on urinalysis results.

Urinary 8-OHdG as a Biomarker for Oxidative Stress: A Systematic Literature Review and Meta-Analysis

“…A background range for 8-OHdG has been reported in different studies for healthy persons [11,[18][19][20]. However, these studies reported a wider range of values, making the identification of background cut-off values challenging.…”

Studying the Association Between Occupational Stress and Urinary Levels of Oxidative Stress Biomarkers (8-OHdG and Biopyrrins) in Brickfield Workers

“…Hence, biopyrrins are known to be possible oxidative stress indicators. 13 The results of the current study showed that the urinary levels of 8-OHdG and biopyrrins were significantly elevated among the exposed brickfield workers when compared with their controls (Table 1). Likewise, a status of increased oxidative stress was observed in a group of Indian brick kiln workers when compared with controls.…”

“…As a result, bilirubin is now thought to be an essential in vivo ROS scavenger. Hence, biopyrrins are known to be possible oxidative stress indicators 13 …”

“…An increase in bilirubin consumption as a result of oxidative stress is reflected in a rise in urinary biopyrrin levels. Because of these properties, urinary biopyrrin might be used as a real-time oxidative stress marker to indicate the body’s redox status 13 …”

“…Because of these properties, urinary biopyrrin might be used as a real-time oxidative stress marker to indicate the body's redox status. 13 Because blood sampling is intrusive and could link with psychological stress, urine stress-related biochemical indicators, such as 8-OHdG and biopyrrins, have recently been better used to measure psychological stress. 14,15 Patients with clinical depression had increasing levels of 8-OHdG in clinical settings.…”