Acrolein is a ubiquitous environmental pollutant that produced by the incomplete combustion of cigarette smoke, forest fires, petroleum fuels, plastic materials, and cooking fumes. Inhalation is a common form of people exposure to acrolein, increasing evidence demonstrates that acrolein impairs the cardiovascular system by targeting vascular endothelial cells. However, the molecular mechanism of the cytotoxicity of acrolein exposure on vascular endothelial cells remains unclear. This work focused on the toxicity of acrolein on human umbilical vein endothelial cells (HUVECs). The molecular mechanism was studied based on oxidative stress, DNA damage response (DDR), and mitochondrial apoptosis pathways. After HUVECs were treated with 12.5, 25, and 50 μM acrolein for 24 h, cell viability, cell colony formation, mitochondrial membrane potential, and adenosine triphosphate content significantly reduced, and acrolein increased intracellular reactive oxygen species, apoptosis rate, and 8-hydroxy-2 deoxyguanosine (8-OHdG) level. Furthermore, p38MAPK and c-Jun N-terminal kinase signaling pathways were activated in response to oxidative stress. Moreover, acrolein induced G0/G1phase arrest, promoted the expression of γ-H2AX, activated the DDR signaling pathway (Ataxia-Telangiectasia-Mutated [ATM] and Rad-3-related/Chk1 and ATM/Chk2), and triggered the consequent cell cycle checkpoints. Finally, the protein expression of Bax/Bcl-2 and cleaved Caspase-3 was up-regulated, suggesting apoptosis was induced by triggering the mitochondrial apoptosis pathway. All these results indicated that acrolein induced HUVECs cytotoxicity by regulating oxidative stress, DNA damage, and apoptosis. This study provides a novel perspective on the mechanism of acrolein-induced cardiovascular toxicity, it will be helpful for the prevention of acrolein-induced cardiovascular disease.

Glyoxal, a reactive carbonyl species, can be generated both endogenously (glucose metabolism) and exogenously (cigarette smoke and food system). Increasing evidence demonstrates that glyoxal exacerbates the development and progression of diabetic nephropathy, but the underlying mechanisms of glyoxal toxicity to human embryonic kidney (HEK293) cells remain unclear. In this work, the molecular mechanisms of glyoxal-induced cytotoxicity in HEK293 cells were explored with network toxicology and cell biology experiments. Network toxicology results showed that oxidative stress and advanced glycation end products (AGEs)/RAGE signaling pathways played a crucial role in glyoxal toxicity. Next, further validation was performed at the cellular level. Glyoxal activated the AGEs-RAGE signaling pathway, caused the increase of cellular ROS, and activated the p38MAPK and JNK signaling pathways, causing cellular oxidative stress. Furthermore, glyoxal caused the activation of the NF-κB signaling pathway and increased the expression of TGF-β1, indicating that glyoxal caused cellular inflammation. Moreover, glyoxal caused cellular DNA damage accompanied by the activation of DNA damage response pathways. Finally, the mitochondrial apoptosis pathway was activated. The results that obtained in cell biology were consistent with network toxicology, which corroborated each other and together indicated that glyoxal induced HEK293 cells damage via the process of oxidative stress, the AGEs-RAGE pathway, and their associated signaling pathways. This study provides the experimental basis for the cytotoxicity of glyoxal on HEK293 cells.