Intervention effect of water‐soluble antioxidant of bamboo leaves on short‐term internal exposure and toxicokinetics of acrylamide in Chinese adolescents
Authors: Chen Xinyu , Wang Qiao , Zhang Yu 
Published: November 2023

Bamboos are abundant in phytochemicals, including flavonoids, phenolic acids, lactones, and polysaccharides, which likely contributes to health promotion. Water‐soluble antioxidant of bamboo leaves (AOB‐w) is used for protecting against free radicals, and has been concluded to a novel natural food antioxidant supplement in China since 2004. This study aims to investigate the intervention effect of AOB‐w on the short‐term exposure and toxicokinetics of acrylamide, a dietary hazardous substance generated during heat processing, in Chinese adolescents.

A double‐blind randomized controlled trial (RCT) was conducted in current human study. The participants, who had passed the questionnaire and physical examination, were randomly divided into AOB‐w intervention group and the placebo control. In the morning of test day, 41 participants (19 men and 22 women) were served with a meal of potato chips, corresponding to a single oral dose of 12.6 μg/kg b.w. exposure to acrylamide, and an edible capsule, which contains 350 mg AOB‐w or the placebo with the same dose. Urine were collected within 48 hours thereafter. The diet was rigorously controlled within 24 hours prior to study till entire study finished. Four mercapturic acid metabolites have been investigated as urinary biomarkers for short‐term internal exposure of acrylamide in human, including N‐acetyl‐S‐(2‐carbamoylethyl)‐L‐cysteine (AAMA) and its sulfoxidized product N‐acetyl‐S‐(2‐carbamoylethyl)‐L‐cysteine‐sulfoxide (AAMA‐sul); and N‐acetyl‐S‐(2‐carbamoyl‐2‐hydroxyethyl)‐L‐cysteine (GAMA) and N‐acetyl‐S‐(1‐carbamoyl‐2‐hydroxyethyl)‐L‐cysteine (iso‐GAMA) from epoxy derivative glycidamide pathway.

As a result, the area under curve (AUC) of toxicokinetics profiles showed a 40% drop from the sum of AAMA and AAMA‐sul in control group (68,113.6 nmol/g urine creatinine × hour) to the value in AOB‐w treated group (40,808.27 nmol/g urine creatinine × hour), and also exhibited a gentle decrease about the sum of GAMA and iso‐GAMA. AOB‐w could inhibit the coupling reaction between acrylamide and GSH, which was also proved by kinetic profiles. Besides, AOB‐w may affect cytochrome P450 2E1‐mediated generation of glycidamide, which is further converted into the non‐toxic 2,3‐dihydroxypropionamide. Classified by demographic characteristics, the peak concentration of AAMA in urine of female participants in AOB‐w treated group (Cmax=969.48 nmol/g urine creatinine) was significantly reduced comparing with the peak concentration in urine of control group (Cmax=1973.4 nmol/g urine creatinine). Thus, the conversion of acrylamide into glycidamide seems gender‐dependent. Furthermore, female participants served with AOB‐w showed a higher AAMA‐sul/AAMA ratio (AUCAAMA‐sul/AUCAAMA=0.859) than the ones served with placebo (AUCAAMA‐sul /AUCAAMA=0.558). Future work should focus on the role of AOB‐w in the generation of AAMA‐sul, which acts as a mercapturic acid biomarker and specifically appears in human urine.