Cellular Stress Pathways Are Linked to Acetamiprid-Induced Apoptosis in SH-SY5Y Neural Cells
by
, ,
Ezgi Öztaş
1,*
,
Mehtap Kara
1,
Tuğçe Boran
1,
Enes Bişirir
1,2,
Ecem Fatma Karaman
1,3,
Engin Kaptan
4 and
Gül Özhan
1 1
Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Istanbul University, Istanbul 34116, Turkey
2
Department of Pharmaceutical Toxicology, Faculty of Pharmacy, University of Health Sciences, Istanbul 34668, Turkey
3
Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Biruni University, Istanbul 34010, Turkey
4
Department of Biology, Faculty of Sciences, Istanbul University, Istanbul 34134, Turkey
*
Author to whom correspondence should be addressed.
Biology 2021, 10(9), 820; https://doi.org/10.3390/biology10090820
Submission received: 20 April 2021
/
Revised: 20 May 2021
/
Accepted: 3 June 2021
/
Published: 24 August 2021
Simple Summary
Neonicotinoids constitute more than one-quarter of the insecticides on the market. Acetamiprid, a widely used neonicotinoid, has been found to be linked with neurological symptoms and there is an urge to understand its molecular mechanisms. It decreased cellular viability in millimole concentrations after 24 h in SH-SY5Y neural cells. Additionally, it increased reactive oxygen species, intracellular calcium and endoplasmic reticulum stress. Since overwhelmed cellular stress can destroy cellular structures and cause cell death, we also evaluated cellular death mechanisms. Acetamiprid induced apoptosis rather than necrosis indicating that cells undergo suicide initiated by self-generated death signals. Even though acetamiprid is considered to be a safe option in the struggle against harmful agricultural insects, these results suggest that the widespread use should be taken under strict control in order not to cause damage to the mammals.
Abstract
Acetamiprid (ACE), a commonly used neonicotinoid insecticide, is correlated with neurological symptoms, immunotoxicity and hepatotoxicity. Cellular stress and damage could play an important role in ACE-induced neurotoxicity; however, its mechanism has not been fully understood. We evaluated the effects of ACE on oxidative stress, endoplasmic reticulum (ER) stress, cellular death, mRNA expression levels of related genes and protein expressions of related molecular mechanisms in SH-SY5Y human neuroblastoma cells. The half maximal inhibition of enzyme activity (IC50) value of ACE was determined as 4.26 mM after 24 h of treatment by MTT assay. We revealed an increase in reactive oxygen species (ROS) production and calcium release. Significant increases were measured in inositol-requiring enzyme 1-alpha (IRE1-α) and binding immunoglobulin protein 90 (GRP90) levels as well as mRNA expression levels of caspase 3, 4 and 9 genes indicating enhanced ER stress. Apoptosis and ER stress-related genes were significantly upregulated at ≥2 mM. Indeed, ACE caused apoptosis and necroptosis while necrosis was not observed. There was a significant increase in the protein level of mitogen-activated protein kinase-8 (MAPK8) at 4 mM of ACE while no change was seen for nuclear factor kappa-B (NF-κB) and tumor necrosis factor-alpha (TNF-α). In conclusion, increased cellular stress markers could be proposed as an underlying mechanism of ACE-induced cell death in neural cells.
