Evaluation of the toxic effects of thimerosal and/or aluminum hydroxide in SH-SY5Y cell line

Abstract

In this study, we aimed to evaluate possible toxic effects of thimerosal, aluminum and combination of thimerosal and aluminum in SH-SY5Y cells. Inhibitory concentrations were determined by MTT assay; reactive oxygen species (ROS) were determined by a fluorometric kit and antioxidant/oxidant parameters were measured by spectrophotometric kits. Nuclear factor erythroid 2-associated factor 2 (Nrf2), norepinephrine (NE), dopamine transporter (DAT) and dopamine beta β-hydroxylase (DBH) levels were measured by sandwich ELISA kits while 8-hydroxy deoxyguanosine (8-OHdG) and dopamine levels were determined by competitive ELISA kits. Thimerosal (1.15 μM) and aluminum (362 μM) were applied to cells at inhibitory concentrations 20 (IC20s) for 24 h. ROS increased significantly in cells aluminum- and aluminum+thimerosal-treated cells. Glutathione levels decreased in aluminum group while total antioxidant capacity and protein oxidation levels increased significantly in aluminum and aluminum+thimerosal groups. Lipid peroxidation increased significantly in groups treated with aluminum and aluminum+thimerosal. Nrf2 levels and DNA damage were significantly higher in all groups while dopamine levels significantly increased in cells treated with thimerosal and aluminum+thimerosal, DAT levels were found to be higher in all experimental groups compared to the control. These findings showed that both thimerosal and aluminum can change oxidant/antioxidant status, cause DNA damage, alter dopamine and DAT levels. Changes seen in cells treated with combined exposure to aluminum and thimerosal are more pronounced. Special care should be taken while vaccinating sensitive populations and safer alternatives for aluminum and thimerosal should used.

Evaluation of possible neuroprotective effects of virgin coconut oil on aluminum‐induced neurotoxicity in an in vitro Alzheimer's disease model

“…In our study, we showed that VCO affects the dopaminergic system positively and the dopamine activity is regulated. Our results are consistent with our previous study, which we have shown that Al exposure dysregulated the dopamine neurotransmitter function (Öztürk et al, 2022). Currently, we suggest that treatment by VCO may reverse this phenomenon and regulate the dopaminergic activity in neuroblastoma cells exposed to both Al.…”

“…The competitive inhibition reaction between the HRP‐labeled dopamine and dopamine without the antibody led to a color change that was inversely proportional to the amount of DA present in the samples. ODs were measured at 450 nm, and the concentration of DA in the samples was expressed in ng/ml (Öztürk et al, 2022).…”

NLRP3 Inflammasome Activation by Oxidative Stress and Its Implications for Vaccination-Related Adverse Events

“…Similarly, we found Nrf2 mRNA expression to be significantly lower in the frontal cortex of ASD subjects 110 . In vitro, aluminum hydroxide increases Nrf2 expression in conjunction with its induction of oxidative stress 111 . Moreover, aluminum citrate inhibits, as well as downregulates the expression of the xCT cystine/glutamate antiporter 112 .…”