Effects of thymoquinone in prevention of experimental contrast-induced nephropathy in rats

This study aimed to show the effects of thymoquinone, which is known for its antioxidant, anti-inflammatory, and renal protective effects in contrast-induced nephropathy.

This is an experimental study in rats. 7 groups were included within the scope of our study: sham-vehicle (n=3), premedication-control (n=6), model (n=6), isolated thymoquinone (n=3+3), low-dose thymoquinone (n=6), and high-dose thymoquinone (n=7). In addition to 48 hr of water deprivation, we pre-medicated the rats with intra-peritoneal indomethacin and L-NAME administration. After premedication, 12.5 ml/kg dose of a high osmolar contrast agent-diatrizoat (Urografin %76) was administrated. Thymoquinone was administrated in two different doses of 1 mg/kg and 1.75 mg/kg for four days intraperitoneally. Renal functions, histopathological differences, oxidative stress parameters, and inflammatory indicators of rats were evaluated at the end of the study.

Significant decreases were observed in levels of serum creatinine and serum BUN with low-dose thymoquinone (1 mg/kg) administration. In light microscopy, significantly less histopathological damage was observed in the low-dose thymoquinone group compared to the contrast agent group. While high-dose thymoquinone is accepted as ineffective biochemically, toxic evidence was identified histopathologically. There were no significant differences between M and TA groups for serum MDA and SOD levels, which were compared to evaluate oxidative stress (P:0.99, P:0.98; respectively). TNF-α, iNOS, and NF-кB gene expressions were not significantly different between all groups (P:0.748, P:0.531, P:0.910; respectively).

This experimental study has demonstrated for the first time the protective effect of the TQ substance for CIN in 1 mg/kg dose, in the accompaniment of biochemical and histopathological data in rats.