Effects of Incubation of Human Brain Microvascular Endothelial Cells and Astrocytes with Pyridostigmine Bromide, DEET, or Permethrin in the Absence or Presence of Metal Salts

Abstract

Gulf War Illness (GWI) is a chronic, multi-symptom illness suffered by over one-third of American military veterans who served in the Persian Gulf War between 1990 and 1991. No current single-exposure scenario accounts for all the symptoms observed in GWI, and instead may be due to a multi-exposure scenario. As a larger effort to understand how one category of multi-exposure scenarios of organic compounds such as nerve gas prophylactic pyridostigmine bromide, or insecticides/pesticides such as N,N-diethyl-m-toluamide (DEET) and permethrin, plus heavy metals found in inhaled dust particles (Al, Fe, Ni, Sr, DU, Co, Cu, Mn, and Zn) might play a role in neural aspects of GWI, we begin this initial study to examine the toxicity and oxidative damage markers of human brain endothelial cell and human astrocyte cell cultures in response to these compounds. A battery of cytotoxicity assessments, including the MTT assay, Neutral Red uptake, and direct microscopic observation, was used to determine a non-toxic dose of the test compounds. After testing a wide range of doses of each compound, we chose a sub-toxic dose of 10 µM for the three organic compounds and 1 µM for the nine metals of interest for co-exposure experiments on cell cultures and examined an array of oxidative stress-response markers including nitric oxide production, formation of protein carbonyls, production of thiobarbituric acid-reactive substances, and expression of proteins involved in oxidative stress and cell damage. Many markers were not significantly altered, but we report a significant increase in nitric oxide after exposure to any of the three compounds in conjunction with depleted uranium.

Review of Design Considerations for Brain-on-a-Chip Models

“…The first step is determining whether the cells and their specific origins are required or desired. Brain microvascular endothelial cell (BMEC) monocultures are suitable for testing toxicity [ 62 ] and proliferation [ 63 ], but this model often lacks the cell-to-cell signaling that is required for BMECs to achieve their full barrier potential [ 64 , 65 ]. Often, when a research question is associated with the brain microvasculature, a BBB model is used to answer mechanistic [ 52 , 66 ] or transport [ 67 ] related questions.…”

Cypermethrin induces neurotoxicity via inhibition of glial cell viability and apoptosis initiation

“…In addition, astrocytes perform a wide range of vital functions, including providing neurons with nutrient substrates, neurotransmitter metabolism, and maintenance of ion balance (Miller, 2018). There is increasing evidence that astrocytes may be involved in the etiology of neurotoxicity of many xenobiotic types making similar science field actual and unstopped (Hoffman & Kalinich 2020;Aschner & Kimelberg, 1991). Like in neurons, a disturbance of the ATPase activity was detected in astrocytes treated with pesticides of several types (Vaalavirta & Tähti, 1995).…”

“…The initiation of programmed cell death is determined by evaluating the expression of proapoptotic proteins of the caspase family, Bcl family, and the relative content of cytochrome C in the cytosol compared to its mitochondrial pool (Tomiyama et al, 2010;Jemmerson et al, 2005). Given that glial cells provide all the needs of neurons to perform CNS functions, cultures of glial cells are considered adequate models for evaluating the neurotoxic effects of modern pollutants (Hoffman & Kalinich 2020;Tykhomyrov et al, 2017). Thus, the determination of apoptosis induction in an in vitro model of glial cells should reflect molecular and cellular damage that may be the cause of the neurotoxicity of pyrethroids.…”