Isothiocyanates inhibit the cisplatin-induced apoptosis and inflammation in human kidney HEK-293 cells

Cisplatin is a widely used drug clinically for the treatment of numerous solid malignant tumors. However, the use of cisplatin has resulted in serious side effects, of which renal toxicity and renal dysfunction are the most common. In this study, we explored the effect of isothiocyanates in cisplatin-treated human embryonic kidney (HEK)-293 cells. Allyl isothiocyanate (AITC) and benzyl isothiocyanate (BITC) are substances found in cruciferous vegetables such as watercress and broccoli. They possess various physiological activities including anti-inflammatory, anticancer and antioxidant. However, the protective effect of AITC and BITC against cisplatin-induced nephrotoxicity has not yet been elucidated.

HEK-293 cells were treated with cisplatin (50 µM) in AITC and BITC (0.3-1.25 µM) in the absence or presence for 24 h. MTT assays detected cell viability, and Hoechst 33342 staining allowed us to observe nuclear morphology changes such as chromatin condensation and apoptotic nuclei. Reactive oxygen species (ROS) detection assays measured intracellular ROS production and the griess reaction assays assessed nitric oxide (NO) production. Western blotting and quantitative polymerase chain reactions quantified corresponding proteins and mRNA.

Cisplatin treatment for 24 h increased the generation of intracellular ROS and NO production compared to untreated cells. In contrast, pretreatment with AITC and BITC significantly reduced intracellular ROS generation and NO production. AITC and BITC also significantly inhibited cisplatin-induced inflammation-related genes expression. AITC and BITC decreased cisplatin-induced mitogen-activated protein kinase (MAPK) protein expression. Pretreatment of cells with AITC and BITC in cisplatin-treated cells downregulated the Bax/Bcl-2 expression ratio, resulting in a dose-dependent inhibition of apoptosis.

Our results suggest that the inhibition of inflammation and cell death via MAPK signaling in HEK-293 cells plays a protective role in kidney damage. Therefore, AITC and BITC may be potential candidates to attenuate and prevent the onset and progression of nephrotoxicity.