Disruption of the integrity and function of brain microvascular endothelial cells in culture by exposure to diesel engine exhaust particles.

Diesel exhaust particles (DEPs), a by-product of diesel engine exhaust (DEE), are known to produce pro-oxidative and pro-inflammatory effects, thereby leading to oxidative stress-induced damage. Given the key role of DEPs in inducing oxidative stress, we investigated the role of DEPs in disrupting the integrity and function of immortalized human brain microvascular endothelial cells (HBMVEC). To study this, HBMVEC cells were exposed to media containing three different concentrations of DEPs or plain media for 24h. Those exposed to DEPs showed significantly higher oxidative stress than the untreated group, as indicated by the glutathione (GSH) and malondialdehyde (MDA) levels, and the glutathione peroxidase and glutathione reductase activities. DEPs also induced oxidative stress-related disruption of the HBMVEC cells monolayer, as measured by trans-epithelial electrical resistance. Taken together, these data suggest that DEPs induce cell death and disrupt the function and integrity of HBMVEC cells, indicating a potential role of DEPs in neurotoxicities.