Development of anin vitro blood–brain barrier model to study the effects of endosulfan on the permeability of tight junctions and a comparative study of the cytotoxic effects of endosulfan on rat and human glial and neuronal cell cultures

Abstract

Endosulfan, an organochlorine (OC) insecticide that belongs to the cyclodiene group, is one of the most commonly used pesticides to control pests in vegetables, cotton, and fruits. Porcine brain microvascular endothelial cells were used to develop a model to study the effects of endosulfan on the permeability of tight junctions in the blood-brain barrier (BBB). BBB permeability, measured as transendothelial electrical resistance, decreased in a dose- and time-dependent manner when treated with alpha-endosulfan, beta-endosulfan, or endosulfan sulfate. Cytotoxicity testing revealed that the three endosulfans did not cause cell death at concentrations of 10 microM and below. The ratio of the average permeability of the filter-grown endothelial cell monolayer to 14C-endosulfan (Pe) going from the outer to the inner compartments with that going from the inner to the outer compartments was approximately 1:1.2-2.1 after exposure to concentrations of 0.01-10 microM. alpha-Endosulfan, beta-endosulfan, and endosulfan sulfate had cytotoxic effects on rat glial (C6) and neuronal (PC12) cell cultures as well as on human glial (CCF-STTG1) and neuronal (NT2) cell cultures. The effects of alpha-endosulfan were highly selective, with a wide range of LC50 values found in the different cultures, ranging from 11.2 microM for CCF-STTG1 cells to 48.0 microM for PC12 cells. In contrast, selective neurotoxicity was not so manifest in glial and neuronal cell cultures after exposure to endosulfan sulfate, as LC50 values were in the range of 10.4-21.6 microM. CCF-STTG1 cells were more sensitive to alpha-endosulfan and endosulfan sulfate, whereas NT2 cells were more sensitive to beta-endosulfan.

Astrocyte activation and neurotoxicity: A study in different rat brain regions and in rat C6 astroglial cells

“…Like rotenone, other neurotoxins viz. 6-Hydroxydopamine, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, paraquat (Raicevic et al, 2005;Kim et al, 2008) and insecticides (Chan et al, 2006;Abou-Donia et al, 2006;Flaskos et al, 2007) induced death of Fig. 12. (a) Images showed the DNA fragmentation in control and treated astrocytes after 16 h of treatment.…”

Ameliorating effect of N-acetylcysteine and curcumin on pesticide-induced oxidative DNA damage in human peripheral blood mononuclear cells

“…Endosulfan causes neurotoxicity by uncontrolled excitation of neurons as well as through the alteration of transmission level (Chan et al 2006). Recently, apoptosis of neuronal cells has been shown to be one of the causes of neurotoxicity as a result of endosulfan exposure (Jia and Misra 2007).…”

A microfluidic model of the blood–brain barrier to study permeabilization by pulsed electric fields

“…However, in vitro models can provide more freedom to explore parameters and offer quantitative data without the complications of animal studies 39 . In vitro models exploit monolayer cultures of cerebral endothelial cells as the main constituent of the BBB, using different platforms such as transwells 40–42 , micro-fabricated membranes 43 , tubes 44 , collagen matrices 45 and microfluidic channels 46–49 to monitor the integrity and permeability of the endothelial cells using tracers 50 , trans-endothelial electrical resistance (TEER) 40, 46 or electrical impedance spectroscopy (EIS) 48, 51 .…”