Wistar Rats Hippocampal Neurons Response to Blood Low-Density Polyethylene Microplastics: A Pathway Analysis of SOD, CAT, MDA, 8-OHdG Expression in Hippocampal Neurons and Blood Serum Aβ42 Levels

Abstract

Low-density polyethylene microplastics are ingested into the bloodstream and distributed to all the organ tissue, including the hippocampus, causing toxic effects. This research aimed to elucidate the responses of hippocampal neurons to microplastic in the blood based on the expressions of superoxide dismutase (SOD), catalase (CAT) enzymes, malondialdehyde (MDA), 8-oxo-7,8-dihydro-2-deoxyguanosine (8-OHdG) in hippocampal neurons, and blood serum amyloid beta 1-42 (Aβ42) levels using SMART PLS pathway analysis. This was a pure experimental research on Wistar rats with a post-test control group design. Five experimental groups (X1, X2, X3, X4, X5) were given 0.0375 mg, 0.075 mg, 0.15 mg, 0.3 mg, and 0.6 mg of low-density polyethylene microplastics mixed in 2cc distilled water, respectively. Furthermore, except for control (C), the groups received microplastics an oral probe for 90 days. The molecular response of hippocampal neurons of Wistar rats to microplastics in the blood significantly decreased SOD enzyme expression, while CAT enzyme was unaffected. It considerably increased neuronal membrane damage (expression of MDA), increased considerably neuronal deoxyribonucleic acid damage (expression of 8-OHdG), and decreased blood serum Aβ42 levels (pathway analysis, all t-value >1.96). The pathway analysis showed that hippocampal neurons were significantly affected by microplastic particles in the blood.