CORRELATION BETWEEN SALIVARY ASCORBATE, GLUTATHIONE, and MALONDIALDEHYDE in HUMAN

Background: Glutathione and vitamin C (ascorbate) are the two main aqueous phase antioxidants, while malondialdehyde is one among the oxidative stress biomarkers studied previously in human body fluid except saliva. Objective: The aim of this study was to determine the correlation between salivary ascorbate, glutathione, and malondialdehyde in human. Methods: Unstimulated whole saliva samples were collected from 22 systemic and orally healthy young adults (10 males, 12 females; age 21-23 years old). Samples were collected from the subjects in a break time before lunch. Salivary glutathione, ascorbate, and malondialdehyde were measured spectrophotometrically. Results: Means±SD of salivary glutathione, ascorbate, and malondialdehyde were 0.93±0.25nmol/mL, 7.1±3.8nmol/mL and 0.07±0.04nmol/mL, respectively. The results indicated a statistical significant positive correlation between salivary glutathione and ascorbate (r=0.67, 95% CI=0.38 to 0.84, p=0.001) while negative correlation were found between glutathione and malondialdehyde (r=-0.7, 95% CI=-0.86 to -0.43, p<0.001) and between ascorbate and malondialdehyde (r=-0.6, 95% CI=-0.81 to -0.23, p=0.003). Conclusions: This study demonstrated that glutathione and ascorbate were positively correlated and the two main antioxidants were negatively correlated with malondialdehyde in human saliva.