Molecular Insights Into Di(2-Picolyl) Amine–Induced Cytotoxicity and Apoptosis in Human Kidney (HEK293) Cells

Abstract

Di(2-picolyl) amine (DPA) is a pyridine derivative known to chelate metal ions and thus has potential anticancer properties; however, its effect on normal cells remains unchartered necessitating further research. This study, therefore, investigated the mechanistic effects of DPA-induced cytotoxicity and apoptosis in the HEK293 cell line. Methods required that an half the maximum inhibition concentration (IC50) was derived using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Analyses aimed to assess oxidative stress, membrane damage, and DNA fragmentation by means of biochemical assays were performed. Luminometry analysis was carried out to understand the mechanism of apoptosis induction by determining the levels of adenosine triphosphate (ATP) and the activities of caspase-8, -9, and -3/7. Western blotting was used to ascertain the expression of apoptotic and stress-related proteins. An IC50 of 1,079 µM DPA was obtained. Antioxidant effect correlated with a minimum increase in reactive oxygen species induced lipid peroxidation. The increase in initiator caspase-8 and -9 and executioner caspase-3/7 activities by DPA-induced apoptosis albeit prompting a decline in the levels of ATP. Furthermore, DPA brought about the following consequences on HEK293 cells: markedly elevated tail lengths of the comets, poly (ADP-ribose) polymerase 1 cleavage, and apoptotic body formation observed in the late stages. The cytotoxic effects of DPA in HEK293 cells may be mediated by induction of apoptosis via the caspase-dependent mechanism.