Inhibition of LPS-induced apoptosis in differentiated-PC12 cells by new triazine derivatives through NF-κB-mediated suppression of COX-2

Anti-inflammatory therapy approaches have been in the focus of attention in the treatment of neurodegenerative diseases, such as Alzheimer's disease (AD). In this study, we examined the role of new 1,2,4-triazine derivatives against cytotoxicity exerted by lipopolysaccharide (LPS) in differentiated rat pheochromocytoma (PC12) cell line. Our results indicated that LPS-induced cell death can be inhibited in the presence of some of these compounds, as measured by MTT test, acridine orange/ethidium bromide staining and caspase-3 expression assay. We further showed that these compounds exert their protective effects through the inhibition of LPS-induced generation of nitric oxide and reactive oxygen species. Triazine derivatives inhibited LPS-induced nuclear translocation of nuclear factor- κB, a known regulator of a host of genes involved in specific stress and inflammatory responses. Pretreatment of PC12 cells with triazine derivatives also suppressed LPS-induced cyclooxygenase-2 expression while up-regulated heat shock protein-70 (Hsp-70). Moreover, the treatment of brain diseases is limited by the insufficiency in delivering therapeutic drugs into brain relating to highly limited transport of compounds through blood–brain barrier (BBB). Using a reliable model based on the artificial neural network, we indicated that these compounds are capable of penetrating BBB and may be useful agents for preventing neuroinflammatory diseases like AD.

Research highlights▶ LPS decreased cell viability of PC12, while 5a–c protected neurons against LPS-induced cell death. ▶ Inhibition of LPS-induced apoptosis by 5a–c was along with reduction of intracellular ROS and NO level. ▶ Inhibition of NF-κB by 5a–c was concomitant with increase of Hsp-70 and decrease of caspase-3 level. ▶ 5a–c decreased COX-2 level in PC12 cells. In contrast, neither LPS nor 5a–d affect COX-1 level. ▶ ANN results indicated that 5a–c have good permeability values.