In Vitro Modulation of Endogenous Antioxidant Enzyme Activities and Oxidative Stress in Autism Lymphoblastoid Cell Line (ALCL) by Stingless Bee Honey Treatment

Abstract

Autism has been associated with a low antioxidant defense mechanism, while honey has been known for decades for its antioxidant and healing properties. Determination of stingless bee honey (KH) effects on antioxidant enzyme activities and oxidative damage in Autism Lymphoblastoid Cell Line (ALCL) was performed. ALCL and its normal sibling pair (NALCL) were cultured in RPMI-1640 medium at 37°C and 5% CO2. ALCL was treated with 400 μg/mL KH (24 h), and oxidative stress marker, malondialdehyde (MDA), and antioxidant enzyme activities (catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD)) were measured via enzyme-linked immunosorbent assay (ELISA), while deoxyribonucleic acid (DNA) damage was determined via comet assay. Low SOD activity ( $p<0.05$ ) and high MDA level ( $p<0.05$ ) were observed in ALCL compared to NALCL. Higher grade (Grades 2 and 3) of DNA damage was highly observed ( $p<0.05$ ) in ALCL compared to NALCL, whereas lower grade (Grades 0 and 1) DNA damage was highly detected ( $p<0.05$ ) in NALCL compared to ALCL. KH treatment caused a significant increase in SOD and GPx activities ( $p<0.05$ ) in ALCL compared to untreated ALCL. Correspondingly, KH treatment reduced the Grade 2 DNA damage ( $p<0.05$ ) in ALCL compared to untreated ALCL. CAT activity showed no significant difference between all three groups, while the MDA level showed no significant difference between treated and untreated ALCL. In conclusion, KH treatment significantly reduced the oxidative stress in ALCL by increasing the SOD and GPx antioxidant enzyme activities, while reducing the DNA damage.